July 2017

Derek K. Tracy, Dan W. Joyce, Sukhwinder S. Shergill

Full text: The British Journal of Psychiatry Jul 2017, 211 (1) 58-59; DOI: 10.1192/bjp.211.1.58


What’s the deal with red hair? You are probably aware that different levels of the pigment melanin determine the complexion of our skin. It’s a similar process with hair colour: those with least eumelanin have blonde hair, those with more have brown hair, and those with most have black hair. You’ll notice one group is absent - one of these kids is doin’ his own thing – red heads. In such individuals a different gene prevents the conversion of pheomelanin to eumelanin; they thus don’t get any of that hair pigment, resulting in a unique colouring. Why do I tell you this, beyond explaining one of nature’s greatest mysteries? To help us understand a wider genetic process known as epistasis: genes impacting each other. In other words, it’s not just the genes you have, but how they interplay that is important. Why should you care? Well scientists have long noted that the background rate of genetic mutations is rather high in humans, so much so that standard calculations predict that we shouldn’t exist as a species. Now even to the most hard core geneticist this clearly presents what might be considered a “major problem”, and infers that maybe the theory might need tweaking – a bit like the mathematics formula that says bumblebees shouldn’t be able to fly. Noting with interest the continued existence of humans, despite their predictions, scientists have thus revisited their work, and come to the conclusion that it is epistasis that keeps us alive as a species: our genes mutate on a regular basis, but they are kept in check by the impact of other genes. Good news for us all, whatever our hair colour.

Finally, one of the Kaleidoscope authors – I can’t remember which one of us – came across a paper that just tickled us right. A team at UCL in North London explored if medical students could predict doctors’ specialities by looking at pictures of them: they also had to rate the doctors’ perceived professionalism and trustworthiness through the photos. The researchers’ underlying interest was trying to determine which characteristics were associated with which fields of practice, and how that might influence medical students’ career choices. Certainly in medicine it has long been established that as well as learning through lectures and formal teaching, trainees subconsciously model their behaviour on senior doctors they trust. Of concern, no women doctors were identified as surgeons, with the medical students (half of whom were female) only assigning that label to photos of men. However, although the paper rightly discusses issues of gender roles, stereotypes and expectation, the other clear finding, and real take home message, was that male psychiatrists were labelled as the best dressed and most fashionable of all the medics. Science has spoken. Now if you’ll excuse me, I have a meeting with my tailor.