January 05, 2011

Model-based prediction of hair color

Human Genetics doi:10.1007/s00439-010-0939-8

Model-based prediction of human hair color using DNA variants

Wojciech Branicki et al.


Predicting complex human phenotypes from genotypes is the central concept of widely advocated personalized medicine, but so far has rarely led to high accuracies limiting practical applications. One notable exception, although less relevant for medical but important for forensic purposes, is human eye color, for which it has been recently demonstrated that highly accurate prediction is feasible from a small number of DNA variants. Here, we demonstrate that human hair color is predictable from DNA variants with similarly high accuracies. We analyzed in Polish Europeans with single-observer hair color grading 45 single nucleotide polymorphisms (SNPs) from 12 genes previously associated with human hair color variation. We found that a model based on a subset of 13 single or compound genetic markers from 11 genes predicted red hair color with over 0.9, black hair color with almost 0.9, as well as blond, and brown hair color with over 0.8 prevalence-adjusted accuracy expressed by the area under the receiver characteristic operating curves (AUC). The identified genetic predictors also differentiate reasonably well between similar hair colors, such as between red and blond-red, as well as between blond and dark-blond, highlighting the value of the identified DNA variants for accurate hair color prediction.



Ponto said...

I am glad some group has put to the test the SNPs claimed to have an effect on pigmentation differences in Europeans, at least in south Polish. There is too much time and speculation put into such banal physical differences.

I live in Australia and mostly among Anglo and Irish Australians. So, those pigmentation features like blue eyes, pale blood pink tinged skin, blond, red, brown, auburn..hair colors are mundane and frankly the norm. It is like selling coal to Newcastle. Humdrum.

It would help if 23andMe tested all those SNPs especially rs1805009 but they don't. As I indicated above, pigmentation issues in Europeans don't interest me much except academically. The aesthetic effects are totally lost on me, however, I was curious about red hair as my children are red haired (I have grown accustomed to it) and I wondered where in the universe it came from. At least 23andMe tells me I am rs1805008 CT. So that must explain the red hair. If my children had "normal" colored hair, the whole pigmentation thing would be totally boring.

Linda Avey said...

It's a pretty well-known fact that redheads, for reasons that may or may not have been fully elucidated, require higher doses of anesthetics. If better knowledge around the genetics of pigmentation adds to a fuller understanding of drug response and other health-related topics, bring it on!