Angelina done gotst her boobies cutted off.

Boobs: they feeds the babes. But, if that’s their primary function, why don’t they just plump up when women need them and shrink when they don’t, as is the case for other female primates? The nubility hypothesis argues that breasts are an adaptation in human females that resulted from sexual selection: men find breasts attractive because they show off a woman’s fat reserves; indicative of her potential as a solid baby carrier.

For some, breasts may be associated with femininity. Perhaps they’re a source of empowerment. Maybe a welcome mat for objectification. Hell, some may just find them a nuisance. Before diving in, stop and consider how you value breasts; not necessarily your own, but boobs in general (doing my darnedest to keep this article gender-neutral). Keep those values in mind as you read further.

In May last year Angelina Jolie was published as a guest contributor for The New York Times announcing in her article, My Medical Choice, that she had undergone a double mastectomy. Jolie’s mother, Marcheline Bertrand, passed away in 2007 at the age of 56 after a battle with ovarian cancer that lasted almost a decade. Although not presenting with any symptoms, but interested to determine her own disease risk, Jolie consented to have her DNA tested for genetic factors associated with increased susceptibility to breast and ovarian cancers.

Test results revealed that Jolie possesses a gene variant (allele) called BRCA1, which confers an 87% risk of breast cancer and a 50% risk of ovarian cancer (as opposed to average risks for women of 12% and 1.7%, respectively). Primarily, she decided to address her increased risk of breast cancer by having both breasts surgically removed. However, in an interview with Entertainment Weekly in March this year, she mentioned there being “still another surgery to have” that she would continue to seek medical advice about. Unconfirmed reports suggest Jolie intends to address her increased risk of ovarian cancer, too, by having both ovaries surgically removed.

Angelina_Jolie_2010_4Colour image courtesy of Gage Skidmore at http://flickr.com/photos/gageskidmore.

Forbes named Angelina Jolie Hollywood’s highest-paid actress in 2009, 2011, and 2013. Although, it was while filming Lara Croft: Tomb Raider in war-torn Cambodia way back in 2001 that Jolie developed an understanding of the world that would motivate her to put her tremendous fame and fortune to better use. Jolie features in the news almost as often now for her humanitarian endeavours as she does promoting films. Just this month she co-hosted a London summit attended by representatives of more than 140 nations seeking to declare an end to sexual violence in war.

Regardless of why her name is being splashed about in the media (if it isn’t her, it’s the power couple she belongs to), Angelina Jolie is extremely high-profile. So, when a public figure makes such a powerful statement in sharing their experiences with genetic testing and drastic preventive surgery, what are the ramifications?

Jolie intended to empower women by alerting them to their options; both in seeking genetic testing, and in addressing increased risk should genetic susceptibility factors be detected. Whilst her bravery was applauded by many for improving breast cancer awareness in general, her announcement may also have instilled a sense of panic in women and set a behavioural trend for those whose worst fears were realised after genetic testing; many high-risk patients hastily leaping to chop their boobs off before thoroughly examining their options (counterproductively limiting some options, rather than broadening them).

This two-part post takes a wee look at err’thang: breast cancer basics and humbling statistics, genetic testing (including the deets on those high-risk alleles), preventive measures, whether Ange’s best intentions were realised in the wake of her revelation and, finally, a romantic perspective on the potentially devastating disease that’s estimated to have taken the lives of 508,000 women in 2011.

A New Mindset for the UN: Jolie, Pitt, Annan and spouseColour image courtesy of World Economic Forum at https://www.flickr.com/people/15237218@N00.

The cell cycle facilitates controlled cell growth and division. At different points in the cell cycle, regulatory checkpoints exist to ensure that advancing in the cycle is appropriate for a given cell, e.g. “Have I replicated all my DNA?” “Have my chromosomes aligned where they’re supposed to?” “Is there enough food around to nourish my daughter cells?” “Is it too cramped up in here to divide?”. If conditions aren’t ideal to advance in the cell cycle, regulatory proteins suspend proceedings to sort things out. However, when specific mutations exist in DNA associated with these checkpoint proteins, cell growth and division becomes unregulated; cells proliferate rapidly with limited differentiation (tumour development).

Cancerous tumours can be characterised by abnormal cell growth with the potential to metastasise (spread from one organ to another). Cancer developing in breast tissue originates most commonly in the milk duct lining (ductal carcinomas) or the lobules that supply the milk ducts (lobular carcinomas). Although typically discovered when a dense lump forms in the breast tissue or armpit lymph node, other symptoms of breast cancer may include skin dimpling, changes in breast size or positioning, skin colour or texture, the appearance of the nipple, or abnormal nipple discharge (a clear or bloody fluid).

The National Breast Cancer Foundation in the US encourages women of all ages to perform ‘breast self-exams’ monthly and they provide a tutorial to aid these little checks. I’d recommend that all readers access the link and give it a once-over, even if it serves merely as an excuse to spend a minute longer in a steaming-hot shower. The New Zealand Breast Cancer Foundation estimates that 60% of young women don’t know the signs beyond a lump, so an even greater percentage of all young people could really benefit from an increased awareness of the broad range of breast cancer symptoms.

But! Keep in mind that symptoms can arise for lots of reasons (not just because there’s an unrelenting population of immortal mutant cells trying to hijack the body from ‘Base Camp Boob’). So, promptly seek medical advice regarding any suspected symptoms (or encourage others to if they disclose their concerns), but try not to flip out prematurely.

Symptomatic patients will receive a physical breast examination from a healthcare provider, who may then request a diagnostic mammogram. Mammograms or ‘breast x-rays’ (or boob-squishing nightmares) are also used in breast cancer screening and are recommended biennially (once every two years) for New Zealand women aged between 45 and 69, but their use is controversial. (Note that diagnostic mammograms involve image capture from multiple vantage points with zoom potential to provide a more detailed scan than a screening mammogram.)

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Mammography involves compressing the breast between parallel plates and beaming low-energy x-rays from a transmitting plate to a detecting plate (either photographic film or a digital detector). The amount of x-ray radiation that passes through the breast will depend on tissue density and composition. Dense breast tissue blocks or ‘attenuates’ x-ray radiation (similar to the way bones do in x-ray radiography) and these areas appear lighter on a developed mammogram.

Breast tumours are characterised on mammograms by high-density, but in women with dense breasts (a lower proportion of fatty tissue to fibrous connective tissue), tumours can be hidden and breast cancer may go undetected. Increased breast density has been associated with an increased risk of developing breast cancer, but it’s likely that this association exists because tumours are so often missed through mammogram screening in these patients (rather than dense boobs necessarily fostering cancer cells).

Ladies will generally have different breast densities (affected by factors such as age and weight),  but breast density can also be influenced by fluctuating estrogen levels during the menstrual cycle. Breasts become more dense late in the cycle when estrogen levels are highest, so it’s recommended that women schedule their mammogram during the first two weeks of their cycle to improve scanning accuracy.

(Highly recommend Deborah Rhodes’ TED Talk, A test that finds 3x more breast tumors, and why it’s not available to you. Seems breast cancer politics can get quite scandalous! Although, I’m a leetle bit skeptical that she stands to make absolutely no financial gain from promoting MBI.)

mammogram-2Colour image courtesy of Memorial Health Services at http://www.memorialcare.org/services/glossary/m/mammograms-digital-mammograms.

Let’s recap. So, if symptoms develop or if areas of concern appear on the screening mammogram of an asymptomatic woman, a comprehensive mammogram will usually be called upon to ‘fill in the diagnostic gaps’. Before we continue, there are a couple of other imaging techniques that you may have heard thrown around a bit.

Breast ultrasound is an imaging technique often used in conjunction with mammography, but not used in breast cancer screening. Ultrasound may miss early signs of cancer like microcalcifications (tiny calcium deposits), but it’s helpful when scanning dense breasts and for non-invasive examination of a suspected cyst.

High-risk patients may also undergo a breast MRI for a more sensitive scan. Increased sensitivity has its downfalls though: use of breast MRI in screening would result in far too many false-positive results; scans detecting suspicious features that turn out to be non-cancerous (not to mention how expensive it would be to equip screening stations with huge MRI scanners and fund use of its technology for so many women).

Anyway, if concerns persist in light of all breast imaging results, a biopsy will be taken so a pathologist can examine cells from suspicious dense breast tissue under a microscope. A technique called fine needle aspiration involves injecting a thin, hollow needle into the breast lesion and sampling cells with a syringe. Alternatively, medical professionals may just decide to whip a whole chunk out of there using a core needle, if not excising the entire lesion! Breast biopsies are commonly guided by ultrasound, so each dense mass can be targeted accurately, but many techniques have been developed; each specialised for tumour size, location, count, and predicted severity.

Pathologists (folks trained to recognise histological ‘red flags’ for cancer) will perform a gross examination of larger preserved biopsy specimens; assessing size, colour, and consistency to surveil for cancer characteristics, and perhaps determine which parts ought to be examined microscopically. Under the microscope, however, they look for things like: weird cells or nuclei (size and shape abnormalities), or a strange arrangement of cells, e.g. cells of glandular tissue in the breast are organised into lobules and ducts, but cancer cells can clump to form either really distorted looking glands, or an aggregate bearing no resemblance to glandular tissue at all. Features identified by the pathologist from the biopsy specimen contribute primarily to breast cancer classification.

To assess how best to treat a given patient and to gauge patient prognosis (likely disease outcome), classification draws on four major aspects of pathology: histopathology, grade, stage, and receptor status (other minor classification approaches exist, too). Histopathology denotes the type of tissue cancer cells were derived from and their spread from that origin, e.g. perineural invasive mammary ductal carcinoma: breast cancer derived from the epithelium lining the ducts of the mammary glands, that has spread to tissue surrounding a nerve.

Grading compares the appearance of cancer cells to normal cells; the less differentiated the cancer cells are (the less they appear like normal cells), the higher their grade and the worse the prognosis. Stages of breast cancer (0-4) are determined using the TNM system: tumour size (T), spread of the tumour to the lymph nodes (N), and metastasis (M); spread of the tumour beyond the lymphatic system. Whereas stage 0 is pre-cancerous, stage 4 is metastatic cancer with a poor prognosis.

Finally, receptor status refers to the receptor proteins expressed on and within cancer cells. Receptor proteins bind signalling molecules like hormones for cell growth and proliferation, but drugs that target these receptor proteins on cancer cells can interfere with hormone-binding, thus meddling in breast cancer development. Determining breast cancer receptor status means the right drugs can be prescribed (with other therapies) to fight the nasty cell population.

Colour image courtesy of cleomiu at http://www.fotolia.com/p/339584.

Although breast cancer can affect males, it is the most common form of cancer for women worldwide. Incidence rates vary from 19.3 per 100,000 women in Eastern Africa to 89.7 per 100,000 women in Western Europe. However, the incidence of breast cancer is increasing with urbanisation and extended life expectancy in the developing world. Survival rates for breast cancer are similarly variable to incidence, ranging from over 80% in North America to less than 40% in low-income countries.

The next post will delve into breast cancer treatment and some of the risk factors associated with breast cancer; both lifestyle ones and genetic factors that have been linked to the disease. Preventive measures will be explored and I’ll take a look at how practical the information about genetic testing actually is in New Zealand, i.e. Is it even available to us? If it is, who’s eligible and is it horrendously expensive? Then Ange will enter the equation once more. We’ll investigate how the general public have responded to her shock announcement and wrap things up by examining the interplay between romantic relationships and the breast cancer journey. Alls the things, plenty to read about alls the things.

Less than a fortnight after Jolie was published in The New York Times, her mother’s younger sister (her aunt), Debbie Martin, passed away at the age of 61 after a cruel bout with breast cancer. Although a tragic passing, I’m sure it would only have reassured Jolie that her decision to sacrifice all she valued about her natural breasts (although cosmetic surgery voided the aesthetic sacrifice) and, furthermore, the decision to share her story with the world was relevant, necessary, and had enormously far-reaching potential.

It’ll be interesting to see how the adverse effects of her announcement might have put a dampener on nothing but a best-intentioned tell-all. However, adverse effects would need to be pretty hefty to outweigh the immeasurable benefits of just getting people talking about their breasts in the first place. Until then!

(And, seriously, check yo’self. Not necessarily thrice-daily, but no harm in working out what’s normal down in the chest region, so you can promptly recognise any curious little changes that pop up.)

I told you: no sex before the election.

It’s election year! So, many of us New Zealanders (for whom it isn’t already glaringly obvious) begin to show our true political colours. But how does donning this political war paint (excuse the hyperbole) affect our romantic compatibility? For those ‘single-and-ready-to-mingle’, how does a prospective romantic partner’s political stance influence your impression of them? And for those already shacked up, how does the impending election perhaps solidify a union, or instead cause a bit of tension? 

Additionally, if politics really do monopolise the game of love to some degree, what determines our political allegiance? Since landmark studies in the 1940s, political scientists have continued to investigate the effects of social environment on political attitudes and behaviour, but only since the 1980s have controversial ‘genopolitics’ studies into the genetic basis of political identity been conducted.

The ideology for some of decision-making in love being conscious and well-reasoned may require a little modification. Accounting for all of the hypothesised environmental and genetic predisposing factors we surrender to somewhat in the dating game (for example, those contributing to our political identities), we may have less control over decision-making in love than we think!

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A few years back in 2011, a pair of political scientists, Huber and Malholtra (from Yale and Stanford, respectively) teamed up to examine the effects of political characteristics on new romantic relationships. They investigated three types of political characteristics: political identity, issue positions, and political engagement; all by analysing messaging behaviour in an online dating community.

A couple of interesting (not-so-)little facts referenced in their paper published in 2012: 74% of single Americans seeking partners reported using the Internet to facilitate dating, and online dating was the third largest contributor to Internet traffic (third only to music and gaming). So, a large proportion of romantically curious American singles were dating online and, evidently, doing a lot of it!

Huber and Malholtra determined that analysing interactions between heterosexual couples where men initiated conversation would generate the largest dataset given their study limits. The pair accounted for confounding variables by sorting members of the online dating community according to their age, geographical location, race, religion, etc.

Results indicated that men sent messages to only 1.4% of women they encountered the profiles of and women responded to just over a third of messages sent to them. In terms of political identity, a liberal man was 31% more likely to message a liberal woman than a conservative woman. Evidence for political sorting by conservative men was even stronger; they were 48% more likely to message a conservative woman than a liberal woman. Positions on the separation of church and state and fiscal issues regarding how to balance the budget were similarly influential, as were self-reported measures of political engagement.

Effects of political characteristics on women’s replying behaviour weren’t quite so dramatic. Women who identified as liberal were only 8% more likely to respond to a liberal man than a conservative man, and conservative women demonstrated only statistically insignificant political sorting. Political sorting for women by issue positions and political engagement was also statistically insignificant.

Based on this analysis in political sorting, women were relatively unbiased in their online dating behaviour. Although some may hastily interpret from this that women were either mindfully accepting or just desperate push-overs to whom politics was foreign, we must consider the role of women in the specific interactions analysed.

As recipients of messages of interest, they would understandably be less biased in their responding behaviour; they might ‘take a risk on someone’ out of flattery or even pity. As instigators in the online relationship, men could be more selective because they couldn’t predict whether women would reciprocate their interest; selectivity wasn’t weakened by promised reciprocity . It would be interesting to turn the tables and see if patterns in relative political sorting between sexes were reversed.

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So, Huber and Malholtra were able to generate evidence to support the concept of political sorting in social relationships (no stretch of the imagination). Online dating provided a unique opportunity for participants to define themselves politically prior to engaging with others, whereas our political identity might not necessarily be something we wear on our sleeve in the real world. Regardless, politics seemed to steer our romantic endeavours somewhat.

What builds our political identity then? For starters, and where a wealth of research is founded, our social environment! Back in the 1940s, Lazarsfeld and associates at Columbia attributed information exposure, political attitudes and, ultimately, voting behaviour to discussion networks of family, friends, colleagues, and acquaintances. As recently as 2002, studies have supported these findings; Beck et al. concluded that these discussion networks largely voted together (even when controlling for socioeconomic status) through dialogue-based influence (persuasion).

But! If Huber and Malholtra’s findings apply to social relationships beyond the romantic, we eventually begin to construct our discussion networks according to our political identity. Therefore, the social environment bearing some of the most intriguing secrets is that preceding conscious political identification; what factors were present before social environment could be steered to perpetuate pre-existing values?

Family constitute the core of most peoples’ discussion networks, and they’re there from the beginning! Family transmission in the development of political identity is significant, but conditional: Jennings et al. (2009) reexamined the concept of family transmission in their paper, Politics across Generations, and results were consistent with studies in the sixties; that children were far more likely to adopt their parents’ political orientations if their family was highly politicised and if political values were reinforced over time.

Although family transmission may stem in part from social interaction, it’s also important to consider the role of the shared economic and physical environments that a family possess. Their political values will likely be influenced similarly by these external factors, regardless of how they influence one another. (But social interests do seem to override others in the ultimate determination of political identity.)

So, parents have the power to breed political minds environmentally, but they may have started the ball rolling when they conceived – no spirited, nightly debates over the dining room table required! Genopolitics aims to determine a genetic basis for our political attitudes and behaviour. Studies in the 1980s assessed liberal and conservative ideologies in identical and non-identical twins and found evidence for political heritability. To test whether this translated to voting behaviour, voter registration records were matched to a Los Angeles twin registry in 2008, which also supported the idea of more shared DNA improving the likelihood of sharing political behaviour (and presumably attitudes).

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Sideline skeptics probably existed from genopolitics’ infancy, but controversy was sparked when Charney and English (of Duke and Harvard, respectively) published Candidate Genes and Political Behaviour in 2012. Regardless of the gene associations they proposed for voter turnout or political preference, many criticised that their “candidate genes” had been implicated in many traits and behaviours. Therefore, adding political attitudes and behaviours to the list was meaningless, because the genes seemed to play some small role in so many things!

Larry Bartels, political scientist based at Princeton and blogger for the Washington Post, doesn’t necessarily doubt evidence supporting a genetic basis for some political attitudes and behaviours, but is unconvinced that knowing this contributes to an improved understanding of politics. Bartels scoffs at the utility of genopolitics in helping us to understand why “support for the death penalty has declined substantially over the past 20 years”, or why “abortion has been a more salient partisan issue in recent political campaigns”.

Also blogging for the Washington Post , John Sides, political scientist at George Washington University, responded to Bartels by highlighting the ramifications of a fixed political identity: the risks of re-writing history or misconstruing information for political benefit (suggesting biological influences may contribute to unlawful or immoral behaviour). Sides then emphasised the potential for improved tolerance of opposing political attitudes with an enhanced understanding of genopolitics: differing views might no longer be seen to exist merely because others are “uninformed or listening to the wrong pundits” (spokespeople), but instead interpreted as predisposed and, therefore, somewhat beyond their control; excusable.

Studies referenced above were all from the US, so how representative their findings are of the political climate in New Zealand is difficult to say. But, if anything, our political identities (to generalise criminally) are probably less pronounced and polarising than the average American. All the more reason to explore politics and develop outlooks of our own (particularly with the general election just around the corner), but not to let those unique political identities rule our social spheres.

Just think! Exercising the sort of ‘tolerance’ (understanding) Sides proposed, but in romance, might drastically expand your dating pool. Although some political differences may turn out to be irreconcilable, interacting with a diverse range of people may just uncover some gems and is a valuable learning experience regardless; expanding our empathetic capacities. Politics can get messy, but a whole bunch of variables contributed to the political identity we each adopt, so it’s a topic that can reveal a lot – whether out on a date or chatting to a co-worker. Read up and share!

Meet at the pizzeria – I’ll be the one who looks just like you.

Pretend for a moment that the burgeoning human population doesn’t threaten our survival on Earth and human cloning is offered to those who want to make copies of themselves, just for kicks. You decide (quite irresponsibly) that it’d be an intriguing experiment. But, say you and your clone eventually demonstrate undeniable romantic compatibility, would you date your clone; should you even entertain the idea of dating your clone?

First, let’s consider the implications of this hypothetical scenario: you’d be significantly older than your clone (whatever age you were at the time you decided to clone yourself), and you wouldn’t necessarily (contrary to the misleading title) look and behave “just like” your clone; even at the same ages, compare the environment you were raised in to the environment your hypothetical clone would be raised in today. Your DNA might be identical, but the expression patterns of genetic elements in that DNA would vary in different environments.

Age difference between donor and clone wouldn’t necessarily be an ‘age ain’t nothing but a number’ issue, but more a potential issue of incest. Would pursuing a romantic relationship with your clone in this scenario be like striking up a love affair with your child or your far younger sibling? As clones of shared sex, no reproductive genetic risk would exist (as would exist for incestuous heterosexuals), but psychological concerns for the clone would understandably prevail.

Admittedly, cloning does bear some genetic risk. Sexual reproduction gives rise to the diversity that enables us to adapt effectively to a changing environment. Therefore, cloning sustainability would be limited by how much diversity we could stand to sacrifice.

Still stewing over all the reasons this hypothetical scenario couldn’t possibly work, but we’ll press on: what’s stopping us cloning humans now; technically and morally, and what you ought to consider if your clone did holler at you on a Saturday night.

Two types of human cloning exist: reproductive and non-reproductive. Reproductive cloning gives rise to a replicate human, whereas non-reproductive cloning generates populations of specific cell types often used for therapeutic purposes.

Although inapplicable to our hypothetical cloning scenario, non-reproductive cloning warrants an entire post. A patient presents with a damaged organ and we want to graft new cells to the site of damage to aid repair. But, to derive a self-sustaining population of specific patient cells, we need stem cells! Taking the appropriate stem cells from the patient would only impede their own repair systems, so we have to create them from more specialised cells.

Plasticity describes a cell’s ability to divide and give rise to different cells types; the greater the variety of cells that can spring from one cell, the more plastic it is. Stem cells are characterised by self-renewal: when they divide, they give rise to a differentiated daughter cell (that may go on to divide and differentiate further), but they also regenerate themselves; their second daughter cell is a replicate. Therefore, they serve as a plastic, self-sustaining source of cells for growth and repair.

Embryonic stem cells have the greatest plasticity. Hidden within the early developing embryo, these incredible wee cells have the potential to create any cell in the body through branching pathways of division and differentiation. In contrast, red blood cells without a nucleus do not divide at all. Other terminally differentiated cells (for example, those on the outermost layer of the skin) may divide initially to regenerate themselves, but will eventually exit the cell cycle and adopt a resting state where they no longer divide either.

To create a human clone or generate a population of specific cells, we want to climb as high on the ladder of plasticity as we can and then (in therapeutic cloning) develop tricks to lead very plastic cells down specific differentiation pathways. Ideally, we could whizz to the top of the ladder and swipe stem cells from developing embryos, but this destroys embryos in the process (massive ethical issues).

Two methods have emerged to create very plastic stem cells from patient cells that are already quite specialised: somatic cell nuclear transfer (SCNT) and induced pluripotent stem cell (iPSC) technology.

SCNT involves implanting the nucleus of a donor body cell (for example, a skin, fat, or liver cell) into an enucleated egg cell (nucleus removed). Sex cells (egg and sperm) only have a single copy of DNA, whereas body cells contain two (one set of chromosomes form each parent). Therefore, reconstructing the egg with double the DNA tricks the egg into thinking it has been fertilised. Shock stimulation is then used to prompt cell division so an embryo develops from the reprogrammed egg.

Embryos are intercepted about 5 days after fertilisation at ‘blastocyst stage’: a thin layer of cells (the trophoblast that will go on to form the baby’s placenta) surrounds a cavity housing the inner cell mass where all the super-plastic embryonic stem cells are!

In reproductive human cloning, an embryo is implanted in the uterus so it can develop to term and be born normally. However, in therapeutic cloning, embryonic stem cells of the inner cell mass are cultured and chemically manipulated to give rise to specific cell types.

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iPSC technology requires that cultured donor body cells be transfected with genes found to confer higher levels of plasticity. Modified viruses act as vehicles to incorporate these ‘stem cell genes’ into the DNA of the donor body cells. However, transfected cells must be carefully selected for because few cells actually incorporate and express the ‘stem cell genes’ to function like embryonic stem cells.

Induced pluripotent stem cells (iPSCs) in culture are prime for chemical manipulation in non-reproductive (therapeutic) cloning – to whip up a batch of pancreatic islet cells, or churn out a population of cardiac muscle cells. But, to reconstruct an entire embryo for reproductive cloning from cells that would only otherwise constitute the inner cell mass presents a pretty hefty challenge.

Tetraploid complementation ropes in a blastocyst donor (in addition to the DNA donor the clone will mimic). Cell division in a fertilised egg forms a two-cell ‘blastomere’. In tetraploid complementation, two blastomeres from an outside donor (perhaps remaining from in vitro fertilisation) are fused and cultured.

iPSCs from the clone master are then injected into the tetraploid blastocyst and the original cells move to the outer to form the trophoblast, while the iPSCs grow and divide to form the inner cell mass. Therefore, the child born would be a clone of the iPSC donor, but would be nourished throughout pregnancy by a placenta derived from cells of an outside donor.

Vast benefits for therapeutic cloning exist, but unless (as our hypothetical scenario suggests) “just for kicks”, why would reproductive cloning of humans be beneficial? Similar to the “saviour sister” conceived by in vitro fertilisation in the Jodi Picoult novel My Sister’s Keeper, clones could be generated as transplant donors for ailing patients (patient age and condition would influence viability). Clones could also be raised in families where parents are infertile or in gay relationships.

Value in human cloning for some rests in the potential for unique companionship, such as the special relationship often shared by twins. Although, others claim donors may just seek to re-write history; rectify detrimental parenting, fulfil dreams never realised. More plausible in arguments for cloning are suggestions that the understanding of cellular differentiation required to crack human reproductive cloning could prove transformative in our approaches to research in health and disease states (for example, cancer and ageing).

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Falling for your clone would, in most of the circumstances above (and similarly in our hypothetical scenario), be like pursuing romantic interests with your child or your pseudo-twin. Traditionalists would likely object and those more progressive may reserve judgement or state liberally something along the lines of, “if the two are mentally stable, consenting adults whose relationship bears no genetic risk to impossible offspring, they have the right to lead the lives they please”.

What then if a donor-clone couple wanted to raise a child of their own, and sought reproductive cloning as a means of doing so? Does the intent with which a clone is generated influence how appropriate we see a potential donor-clone relationship as being?

Such a relationship wouldn’t necessarily be sought by a narcissistic donor either; this immediately sprung to mind when I considered lonesome donors seeking a clone purely for companionship. If you consider how different twin siblings can be, in pursuing a clone relationship, the donor is by no means guaranteed to essentially date themselves. (Whether this would be their understanding is uncertain.) This alternate scenario is unethical in so many ways, blame Her – it’ll broaden your (un-)romantic imaginative capacity.

Non-reproductive cloning has enormous potential, but is plagued by inefficiency. Reproductive cloning is equally as inefficient, morally overwhelming, and would require heavy regulation if it were, in any capacity, to be legalised. (Particularly where iPSC technology is concerned, introducing ‘stem cell genes’ into donor body cells has been associated with a heightened risk of tumour development.)

As for dating clones, “just for kicks”-cloning would (hopefully) never fly and neither would cloning with romantic intent, so if a donor and their clone were to fall for one another, its occurrence would be just as likely as incest or any of a range of other rare paraphilias.

Our hypothetical scenario stated that you and your clone “eventually demonstrate undeniable romantic compatibility” and only then are you confronted by the prospect of dating them. Romantic intent is absent and you develop feelings for each other somewhat inconveniently. So this moves from being a trivial, futuristic ‘date-your-clone’ question, to an awkward question of whether you’d pursue feelings that arose where they weren’t supposed to?

For centuries, men and women attracted to the same sex were shunned from society; discriminated against for having feelings that sprouted where they ‘weren’t supposed to’. Paraphilias we ‘know’ now are ‘wrong’ (for example, pedophilia and zoophilia) are distinguishable because one subject in the relationship is perceived as vulnerable; not consenting (with a fully-developed, high-functioning brain). Such vulnerability for the younger subject in incestuous relationships (even when both are technically consenting adults) stems from grooming potential in childhood.

Do lines blur when romantic intent, grooming (definitions of this will vary), and reproductive genetic risk are absent, but two lovers are still fundamentally linked at a genetic level? Just a thought and thankfully , with regards to human cloning at least, a problem we probably won’t be confronted by in anything but an abstract sense in our lifetimes. But it prompts us to look at what we find ‘romantic’ and what we find perhaps ‘repulsive’. How much is well-founded and how much is spoon-fed to us by society?

LATEST: Unrequited love pandemic.

“In the arithmetic of love, one plus one equals everything, and two minus one equals nothing.” Mignon McLaughlin, The Second Neurotic’s Notebook (1966)

Unrequited love is miserable, but it unites mankind. Most can reflect (perhaps not so fondly) on an instance where their affections have been unreciprocated by a love interest. Reminders that others have felt equally, if not more, inadequate, vulnerable, and insecure, are comforting and serve as a minor consolation in light of rejection.

Demand for such reminders is evident in the countless songs, books, plays, television programmes, and films where unrequited love is woven into the narrative: songs Creep by Radiohead and I Can’t Make You Love Me by Bonnie Raitt, Shakespeare’s Twelfth NightForrest Gump, John Hughes’ Pretty in PinkMiddlemarch by George Eliot, F. Scott Fitzgerald’s The Great Gatsby, and, more recently, 500 Days of Summer and the television series New Girl. Writers exploit these storylines because audiences can relate to them and (regardless of whether audiences are willing to admit it) they often find comfort and derive hope from the romantic misfortunes and recoveries of others.

If we refer back to the definition of romance: the excitement associated with the mystery of love, it’s unsurprising that unrequited love conjures romance in the admirer. Mystery in unrequited love balances on whether the enamoured individual succeeds in winning the affections of their love interest; whether the couple is able to establish a love relationship where exchanges are equal. How romantic  unrequited love is for the recipient will depend on how conscious they are of their admirer and how great the dependence imbalance between the two is.

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Research groups across the US (Bringle et al., 2013) set about identifying different types of unrequited love on a spectrum of interdependence. Interdependence (how much two people depended on one another) was gauged by influence, behavioural control, and the frequency, diversity, and length of interactions between a pair.

Five types of unrequited love spanning from low to high interdependence were identified. Although the interest of the admirer changed little across the spectrum, the varied engagement of the love object influenced overall interdependence.For example, a person with an imaginary lover was illustrative of low-level interdependence, whereas high levels of interdependence were demonstrated in couples where a love relationship existed, but was unequal.

Seven characters have been adapted from the types of unrequited love identified in these psychological studies. Scan through the list of these characters and see which apply (or may have once applied) to you.

1. Starstruck: these victims of unrequited love develop a crush on an unavailable love object; someone they have little or no chance of forming an equal love relationship with, e.g. an imaginary lover or a celebrity. At the low end of the interdependence spectrum, more behavioural control is exercised over starstruck characters, although there may still be an inter-dependence. For example, celebrities may be influenced by superficial interactions with their enamoured fans; changing their behaviour to appeal more to a particular audience.

2. Admirer from a distance: objects of affection for admirers from afar may be more accessible (not necessarily inanimate or famous), but these decidedly ‘unlucky-in-love’ folk will never pursue their romantic interest. Examples of such unrequited love may exist at school or in the workplace and potential occasional interactions could increase levels of interdependence. However, alternatively, the object of desire may never acknowledge their admirer’s existence.

3. Lingerer: essentially an ‘admirer from a distance’ who musters the courage to pursue their love interest, but will only do so passively (e.g. increasing contact, making occasional awkward conversation). Because these pseudo-advances are unclear (although the lingerer believes they’re being quite forward), romantic intentions may go unnoticed by the love object and this will affect the degree to which the admirer and the admired interact and are influenced by each other.

4. Lovestruck: this character, too, begins as a stranger to the love object, but a sudden attraction (“love surge”) commands that the lovestruck individual go about expressing their romantic interests immediately (e.g. asking them on a date). Often referred to as ‘love at first sight’, subsequent romantic gestures in this type of unrequited love may be met by outright or continual rejection. Alternatively, the love object may agree to a date or even enter into a love relationship (almost in a pitying sense and/or in hopes that their feelings will grow to match their admirer’s).

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Disclaimer: use of the term “friend-zoned” here is gender-neutral and suggests nothing of the love object, nor anything about the role of sex in an equal love relationship. Also, the term describes a relationship at a given time, but is dynamic and subject to change (thus keeping the mystery alive) (See E J Dickson’s 6 Reasons the “Friend Zone” Needs to Die.)

5. Friend-zoned: unrequited love described in the Bringle et al. paper regarding the development of “romantic inclinations” within a friendship context was limited to platonic relationships. However, unrequited love for this character may also spring from a ‘friends-with-benefits’ relationship. Interdependence increases dramatically for these pairs (whether friendship is sexual or not) because their interactions are more frequent and lengthy than strangers. Influence over one another is generally greater, but even more behavioural control is exercised on the friend-zoned; thus enhancing their expectations and worsening their potential ‘fall from grace’ upon rejection.

6. Pining for past lover: break-ups are rarely a “mutual decision”. The unrequited lover in this scenario will often continue to invest and find satisfaction in the relationship, devalue other romantic prospects, profess their continuing affections for an ex-lover, and perhaps even stalk them. Romantic history makes for mammoth interdependence, particularly when interactions persist after dissolution of the relationship. “Frustration attraction” describes the increased passion elicited in response to rejection, and efforts to elucidate a biological basis for this response are currently underway at the State University of New York.

7. Unequal lover: unrequited love for these characters demonstrates an interdependence maximum; a love relationship exists, but the unequal lover is ‘way more into it’ than the object of their affection. These relationships are incredibly dangerous because dependence imbalances, although unarguably detrimental to the unequal lover’s well-being, may be bearable if the shoddy relationship is beneficial in other ways (e.g. advantageous financially or in a wider social sense). Even more dangerous are situations where these collateral benefits are non-existent and it is the unequal lover’s overwhelming affection for their partner that keeps them hanging in there.

Unrequited love occurred four times more frequently than equal love over a two-year period in a group of just over three-hundred highschool and university students in North Carolina. Experiences in unrequited love were subjective; the insecure were more likely to perceive an unfavourable imbalance (“I’m alone in life, I’m constantly shunned by those I’m attracted to“), whereas some overconfident participants may have embellished their relationship balance (“We’re in a really good place right now, we’re planning to travel over the summer“).

All that can really be concluded from these results is that often when we develop feelings for someone, they won’t feel the same way back. However, our frequency of encounters in unrequited love will likely be proportional to how often we fall in love in the first place (our propensity for love), i.e. falling in love all the time means you’ll run into a greater number of dead ends (well, road blocks at least, if only temporary).

In the same North Carolina study, it was determined (as one might expect) that all types of unrequited love were less emotionally intense than equal love relationships. Passion, willingness to sacrifice, and commitment were also less intense in all types of unrequited love. But! Unrequited love registered as more intense on one scale in particular: turmoil. No surprises there.

Previously, “victims” of unrequited love were always the admirers. But, we must also account for the impacts of unrequited love on the recipients of unwanted affections. Writing for the New York Times, Daniel Goleman reminded readers that unrequited love could be painful for the rejecter as well as the admirer; experiencing anxiety, frustration, and guilt at not reciprocating another’s feelings. Perhaps this contributes to higher-level interdependence where engagement from the less-interested is greater.

This all seems quite gloomy and unromantic, but to wrap on a pleasant note, I’ll quote early 19th century New York writer, Washington Irving:

“Love is never lost. If not reciprocated, it will flow back and soften and purify the heart.”

Unrequited love is a bitch at any register on the interdependence spectrum, but it not only unites mankind in a collective sense, it serves in individual character-building; asking us to reevaluate what we have to offer and what we expect from others in return. Live and learn – embrace the unrequited love pandemic!

OCL: Obsessive-compulsive lurve.

The pursuit of love should not become an obsession. Hell, sometimes I regret adopting the pen name The Romantic Geneticist because repeated talks of romantic compatibility and the sensationalisation of love can embarrassingly take a turn for the Taylor Swift:

“I think about love all the time. I have done since I was able to comprehend what love was. I daydream about it all the time.”

“Even after your heart explodes into a million pieces and you’re thinking, “Why did this have to happen?” You make eye contact with someone across the room and it clicks. Bang, you’re in love again.”

Wow. Anyway, this preoccupation for some with finding love begs the question of whether love isn’t in itself just glorified obsession. Perhaps another factor influencing our propensities for love is how easily we become fixated on things?

Like all complex traits that cannot be attributed to single genetic factors, obsessive behaviours can be plotted on a spectrum ranging from ‘cutesy and affectionate’ to ‘psychotic and dangerous’. Recurring thoughts of someone you’ve developed a wee crush on wouldn’t be considered obsessive. And somewhat of a compulsion to text that person would probably serve in your favour if you’re to hint at your interest.

But! Throw a few genetic misprints and brain signalling hiccups into the mix and obsessive-compulsive behaviours might become a little less excusable…

How exaggerated these behaviours are will depend on how many associated genetic factors are present in our DNA, what specific combination of these genetic factors are present, and what environmental factors exist to influence the expression of these factors.

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Meet Sarah and John. Both exhibit some degree of obsessive-compulsive behaviour and have had their DNA tested and a brief life history recorded.

Let’s say that distinct mutations in genes A, B, and C have been implicated in the development of obsessive-compulsive disorder (OCD). Some environmental factors associated with OCD include low socio-economic status, overprotection or emotional neglect in childhood, sexual abuse, and having parents with poorer mental health.

Sarah possesses all three genetic variants linked to OCD, but she grew up in a wealthy family with parents who neither coddled nor neglected her. She didn’t report exposure to any of the other significant environmental factors associated with OCD either.

John doesn’t possess any of the ‘OCD’ variants in genes A, B, or C, but he ticked all the boxes for environmental risk factors in obsessive-compulsive disorder: he was sexually abused at a young age, before being abandoned by an alcoholic mother in a poor neighbourhood.

So who demonstrates the most dramatic obsessive-compulsive behaviours? Whose obsessive-compulsive behaviours are romantically advantageous (perhaps even endearing), and whose behaviours arguably exceed what is deemed socially acceptable. God, it would make for a far more interesting story if I could say with certainty.

Complications arise because the predisposing factors associated with obsessive-compulsive disorder (whether genetic or environmental) are not necessarily unique to OCD. For example, variants in the gene encoding a specific dopamine receptor, DRD4, have been linked to OCD. But! If you recall, similar variants in DRD4 also segregated significantly with eating disorder sufferers (mentioned in previous post, Eating disorder a bit of a romance killer.)

Environmental risk factors can be even less disorder-specific. Sexual abuse, for example, predisposes to an enormous list of psychiatric disorders including depression, attention deficit hyperactivity disorder (ADHD), eating disorders, schizophrenia, and bipolar disorder.

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Given these complications, I’ll predict that Sarah will exhibit obsessive-compulsive behaviours at the lower end of the spectrum, i.e. she thinks of John often and seems uninhibited in her displays of affection toward him. When Sarah isn’t in John’s company, she’s regularly in contact with him by other means, and she factors John into most significant decisions she makes.

However, Sarah isn’t anxious to please him, she maintains relationships with her own family and friends, she pursues her own interests, and although she doesn’t like the thought, she’d eventually move on if the two were to separate.

John may not have possessed genetic factors associated with OCD, but the environmental factors he was exposed to as a child put him at incredibly high risk of developing other psychiatric disorders, if he possesses genetic variants linked more specifically with them. Therefore, John’s obsessive-compulsive habits may not be as pronounced as Sarah’s, but the likelihood he’ll experience some form of mental illness will be high, e.g. he might grapple with alcohol addiciton.

Evolutionarily, if moderate obsessive-compulsive behaviours have benefitted our romantic lives, it isn’t surprising that genetic factors associated with OCD have been selected for in nature. Additionally, ‘OCD’ genetic variants promote a meticulous nature; great attention to detail, and have been linked to above-average intelligence in some studies.

Seems that so long as we can avoid too many of the genetic and environmental contributing factors (or powerful combinations of these), being a little OCD ain’t too bad. Although, surrendering to the adoration you have for someone is one thing, letting those romantic tendencies monopolise your single life is another. Obsessions with finding love – flag! Romantic curiosity – absolutely, why not! There’s a difference.

Crazy in love.

Granted, love is subjective and dynamic. But, if you’re fortunate enough to have ‘been in love’, think on that romantic experience (or those experiences). Consider the time it took for you to ‘fall in love’ and how sensational those feelings were at their peak.

Even if you were to encounter your hypothetical ‘perfect match’, what determines how fast and how hard you fall? Perhaps yet another factor influencing romantic compatibility is matching peoples’ propensities for love in general.

An article published in EMBO Reports early in 2013 reviewed The biochemistry of love: an oxytocin hypothesis. Behaviours “at the heart of love” such as eye contact and social cognition were attributed to “intricate molecular dances” between signalling molecules in the brain called oxytocin and vasopressin.

Vasopressin contributes to the physical and emotional mobilisation required in defensive behaviours; those involved in protecting a lover. In contrast, oxytocin signalling stimulates relaxed physical states; those associated with free-flowing social engagement and good sex.

The systems in the brain regulated by these signalling molecules are sometimes redundant; if one doesn’t do the trick, the other will chime in. However, in order to induce a significant reduction in social engagement, studies in voles suggested that both systems had to be blocked. Therefore, to be genuinely unenthused in love, at least a couple of biochemical roadblocks must be struck.

Unsurprisingly, given how interwoven their roles at a biochemical level seem to be, genes regulating the production of oxytocin and vasopressin are located on the same chromosome. This promotes coordinated synthesis and secretion of these signalling molecules – a more intimate biochemical dance!

Oxytocin and vasopressin contribute in some way to the sensation of love, but the biochemical love web is vast and complex. By shedding a little light on the biochemistry of love, I hoped to provoke some thought as to the potential genetic basis for the traits of those deemed ‘head-over-heels’ romantics or ‘borderline-asexual’ pseudo-romantics.

Perhaps mutations affecting genes involved in oxytocin and/or vasopressin signalling in the brain influence whether we identify as one or the other. Maybe, given certain environmental factors, these genetic anomalies manifest to dramatically alter our respective pools of ‘romantically compatible’ human beings.

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Is matching people on the basis of their propensity for love a matter of opposites attracting? For example, Joe falls in love fast and when he does, his feelings seem beyond his control. Joe’s friends tease him for getting so hung up on the guys he dates. Whereas Mark doesn’t fall in love quite so easily and when he does, his displays of affection remain relatively reserved. Mark’s friends have nicknamed him the Ice Queen.

Joe could be intrigued by Mark’s closed-off nature and thrill in the challenge of breaking through this ‘hard shell’ of his. However, a happy ending in this scenario would require that Joe finds reward enough in Mark’s occasional subtle displays of affection.

If opposites attract, Mark could find Joe’s overt displays of affection entertaining and humour how he seems to be swept up into love. Although, he’d need to be able to tolerate Joe’s persistent attempts to win his attention.

On the contrary, perhaps matching people on the basis of their propensity for love is more a matter of likeness. Joe might be better suited to someone who reciprocates his overzealous displays of affection. Similarly, Mark might find more comfort in companionship with someone who, too, finds love pleasant, but doesn’t necessarily tumble madly into love.

An enormous caveat to this analysis is that people play pretend. A character like Joe might be overcompensating for lacklustre feelings of love by exaggerating his displays of affection. He might be afraid he hasn’t experienced what his family and friends have, or what he sees in the movies, and wants to mimic this to reassure himself he isn’t weird.

Likewise, Mark might be masking his feelings of love because he feels threatened by how overwhelming they can be. Perhaps he fears surrendering control to something he can’t define and despises the irrationality love summons in him.

Because what we interpret from someone’s behaviours can be unrepresentative of what is actually occurring on a genetic and biochemical scale inside their body, match-making on the basis of propensity for love is best left for pondering. It should not serve in any practical capacity – even if statistics were to suggest that opposites attracted or those more alike were better suited to one another!

It’s a harsh reality, but it’s becoming increasingly salient with each post: romance is all trial and error. Accept it and get amongst for better or worse, or forfeit romance for emotional safety.

Become citizen scientists in the study of romance and conduct some trials of your own!

Homebodies and nomads.

Mum was three years Dad’s junior. The two attended the same high school, but didn’t meet until Dad had long since ditched formal education to complete an automotive mechanic apprenticeship and Mum was sitting her sixth-form school certificate. Dad self-deprecatingly romanticises his first meeting with my sixteen year-old mother, “Our eyes met across a smoky nightclub dance-floor.”

Regardless of how Dad might mock his initial encounter with Mum, a romantic relationship sprung from that meeting that was fun and fast-paced. Having both joined the workforce, Mum and Dad moved out of their family homes and closer to the city to flat with friends and it wasn’t long before they decided to cross the ditch to Queensland. Their departure was marked by a joint celebration of Dad’s 21st and their engagement – they were young and brave and in love.

Mum and Dad settled in a north-western Brisbane suburb and only returned to New Zealand a few years later to be wed in front of family and old friends. I was the fetal flower girl; not showering the bride’s path in flowers, but instead serving as a symbol of my mother’s deflowering (apologies to my grandparents). Four months down the track I marched out of the womb to greet the world and my sister followed two-and-a-half years later.

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Memories of Brisbane could be likened to life on Ramsay Street in the Australian television series Neighbours. Mum worked as a bank teller. Dad worked as a mechanic and later established a water-blasting business. We lived in a cul-de-sac where all residents were like family. On Friday nights the blokes cracked into a few beers around the barbecue before migrating indoors to watch the footy, the shielas tippled in a wine or two around the patio and gossiped about work and neighbourhood goings-on, and the children played outdoors; swimming, riding bikes, skateboards and rollerblades, trampolining, catching insects and toads, spying eels and snakes creekside.

But it wasn’t to last. I was three years old and my sister barely nine months when Mum decided to leave Brisbane with the two of us. Mum missed New Zealand. She yearned for the familiarity of home and the support of her parents when confronted by motherhood herself. Dad wanted to stay in Australia. He was excited to explore business prospects there and enjoyed the suburban Queensland lifestyle.

They may have been living under the same roof, but in their minds, to reference another Australian television soap on which I was raised, my parents were… Home and Away. Yes, I did just butcher a heart-rending narrative corner-turn, I’m sorry. Maybe I’m feeling emotionally vulnerable and needed to lighten the mood. Or maybe I just couldn’t resist including such a pithy pun.

Anyway! Were my mother’s homing instincts and my father’s restlessness a genetic recipe for disaster? What genetic basis underlies the traits of a homebody and a nomad, and do these genetic predisposing factors render some couples romantically incompatible?

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Homebodies are defined as people who like to stay at home and are often perceived as unadventurous, whereas nomads are known to roam from place to place; considered ‘hard to pin down’.

Most of the research existing to suggest a genetic basis for homebody characteristics has been conducted in model organisms such as the monarch butterfly, and the queens of ant and bee colonies. Neurobiologists at the University of Massachusetts have been investigating the expression patterns of two populations of monarch butterflies: one migratory and the other stationary.

In the autumn (commencing in September in the US and Canada), hundreds of millions of these butterflies travel south to forests in central Mexico for the winter. Although, when summer arrives in June, the same species of butterfly will stay near their hatching place and reproduce.

Because butterflies may be migratory or stationary seasonally, they all share the genes required to exhibit nomad and homebody characteristics. Therefore, to determine why one population moves and the other does not, it’s necessary to interrogate the gene expression patterns of these populations. If certain genes exhibit markedly different expression levels in the migratory and stationary butterfly populations, this implicates them in the signalling pathways associated with migration.

Migratory and stationary butterfly populations exhibited significantly different expression levels in 40 genes, but only two of the genes had functions related to migration: one facilitated day-night responses in the butterfly and the other was involved in movement.

Queens of bee and ant colonies could bear evidence suggesting an underlying genetic basis for homebody characteristics, but most studies in these model organisms focus on the altruistic nature of female workers who sacrifice their own reproductive potential to rear the offspring of the queen – would seem evolutionarily counter-intuitive.

Unfortunately, homebody characteristics in these model organisms (particularly when exhibited seasonally) manifest through vastly different physiological systems. For example, where butterflies stay close to home in response to changing environmental sensory stimuli (day-length, temperature).

However, we can still take clues from these model systems – similar environmental factors may very well contribute in some way to homebody traits in humans, but research in varying reproductive hormone levels between stationary and migratory model organisms could prove extremely relevant for humans – is it our baby-making desires enhancing our homing instincts?

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And what about the nomads? What genetic and biochemical madness makes them so difficult to keep in one place?

Some nomad characteristics are similar to symptoms exhibited by those diagnosed with attention deficit hyperactivity disorder (ADHD). It turns out that mutations in a specific dopamine receptor gene identified in many with ADHD have also been found in a group of Kenyan nomads!

Dopamine is a signalling molecule in the brain associated with reward-motivated behaviours. When dopamine signalling is impaired, often reward-seeking behaviours become more extreme to elicit the same reward response in the brain.

In many of the traditionally nomadic Ariaal people of northern Kenya (and many in Western civilisation with ADHD), mutations affecting expression levels of a gene DRD4 (dopamine receptor D4) mean that lower levels of the receptor are present in the central nervous system to respond to the dopamine released in reward-seeking behaviour.

Perhaps nomad characteristics in humans are the result of an imbalance in chemical signalling in the brain. If a nomadic lifestyle influenced romance in ancestral nomad populations and continues to affect romance for men and women of the twenty-first century, why have its genetic components survived through evolution?

Turns out that mutations in DRD4 in the Ariaal people didn’t only aid in their roaming behaviour, but also reduced their likelihood of becoming malnourished! However, the same benefits look shaky in settled Ariaal communities. It seems the environmental changes encountered during the transition from a nomadic existence may have been sufficient to reverse the nutritional benefits of mutations in DRD4. In groups of settled Ariaal people, these mutations are associated with an increased risk of malnourishment! Investigating these associations in the impoverished of Western civilisation (where malnourishment is of greater risk) would be interesting – has transitioning into the first world maintained this benefit reversal in those with ADHD, or has another shift occurred?

I went wandering there for a bit, but let’s bring this thing home. Sorry, this isn’t a sign of things to come, I promise. Let this post serve as my sole opportunity for pun-indulgence.

There is (although undefined at present) some genetic basis for homebody and nomad characteristics. In order to identify as a homebody or a nomad, many genetic and environmental criteria must be met. Therefore, even if you were genetically profiled as ‘predisposed to demonstrating homebody- or nomad-like behaviours’, you aren’t doomed to end up as one or the other.

And even if two people were to present with these seemingly polar characteristics, they aren’t definitive of romantic compatibility! Just as the environments we’re exposed to change, so do the characteristics we exhibit – our personalities are dynamic! It’s all about cracking the old timing. Mum and Dad didn’t get it quite right, but communication probably played as much of a role as timing did there.

Although my parents may not serve as prime examples of a homebody and a nomad (Mum was by no means unadventurous – she was nightclubbing at sixteen! – and Dad was still quite prepared to settle down, but only where he wanted to), their story still demonstrates how some characteristics aren’t necessarily compatibility-defining; but they make getting the timing right a hell of a lot more difficult! Genetics is only a small part of the very complex puzzle that is match-making in love.