Expert: Sophia Jane Carter - 1/25/2008

Question
QUESTION: I'm wondering how I ended up a red head?

My mother is middle eastern (dark hair/eyes), and my father is of northern european descent (light hair/eyes).  I have red hair (not auburn), freckles, and brown eyes.

I've heard one needs a red hair gene from both parents to show the trait, but I don't know of any red heads in my mother's family (all have dark hair/eyes).

Is it still possible I received a red hair gene from my middle eastern half as well?  

Thanks!

ANSWER:   The highest frequency for red hair and the gene for red hair is found in western and northern Europe, however redheads aren't exclusive to these regions.  For example, Pashtuns, an ethnic group found in parts of Iran and Afghanistan, are notorious for producing redheads.  Kurds, too, are known to sport red hair.  The ancient Tocarians often depicted themselves and were depicted by others as having red hair.The gene for red hair is present in many Middle Eastern and Central Asian ethnic groups.

You did not mention what ethnic descent your mother is, but it is possible that she has the gene for red hair. Since the gene(s) for red hair is recessive, it is plausible that she and (possibly other family members) may have red hair lurking in their genotype without actually having red hair. This recessive genes mixed with your father's and wham--you.

  Red hair is the rarest natural hair colour in our species.  You should take pride in being one of 2% of the world population that has this phenotype.  :-)


---------- FOLLOW-UP ----------

QUESTION: That is fascinating, thank you for the response!  My mother is in fact Kurdish.

One last question--did red hair originate in the Middle East/Central Asia, or
is it the product of migration from celtic regions?  Or does anyone really
know?

Thanks again!

Answer
Red hair is most common in the British Isles, with a full 13% of the Scottish population possessing the phenotype for red hair and at least 40% of the population carrying the gene.  It is easy to see why red hair is often associated with Celtic origins.

Red hair is a pretty new for us humans--scientists estimate that the gene for red hair has only been around for about 50,000 years, a pretty short time all things considered.  Geneticists believe that a mutation of the melanocortin-1 receptor (MC1R) lead to the rise of red hair.  Northern European groups that invaded and settled the British Isles likely carried the mutated gene.  

Two factors contributed to the gene being dispersed in these groups:  geographic isolation (island separated from mainland Europe) and genetic drift.  Genetic drift is when, by chance, a trait becomes firmly established with a population due to there not being any selective pressure against it.  

This is a plausible theory, however it doesn't quite explain how red hair evolved in other population where there are no records of Celtic expansion.  New evidence has found that  Neanderthals had the gene for red hair.  There is still some lingering debate on whether Neanderthals were in fact just early Homo Sapiens Sapiens (us!), or whether we interbred as two distinct groups. Scientists in favour of the Neanderthal origins of red hair point out that Neanderthal groups spread throughout the Middle East and Central Europe, and as far east as China.  Still others speculate that the gene didn't come from Neanderthals but developed independently in both groups.  The gene was present in early humans as we migrated across the planet.  Genetic drift or some form of positive selection may have caused the gene to propagate more in some  regions and ethnic groups than others.

My personal theory is that the mutation for red hair originally arose about 50,000 years ago on the Eurasian Steppes, and some tribes/groups/ethnicities migrated west (Europe), while others headed back towards the Middle East.  These migrations spread the gene.  Red hair eventually became fixed within northwestern Europe due to genetic drift.

Hope that wasn't too convoluted! Red hair is a serious business. ;)