Red Alert!

by endlesspsych

By Keir Liddle

According to the Telegraph and the Daily Mail new research has claimed that “Bad weather has been blamed for Scotland having ‘more people with ginger hair” – The Mail reports this without any qualifiers however the Telegraph opens the article with the following:

The non scientific research…

Which raises some eyebrows, strawberry blonde and otherwise, to say the least – so what’s the story here? Is this an example of bad science or bad journalism?

Is it time to step up to red alert?

Well it seems the root of the story is this article that Emily Pritchard (an Edinburgh University Student) wrote for the January issue of EUSci speculating why the Scots have the highest proportion of red heads world wide.

Worldwide around 1-2% of the population have red hair this percentage jumps to somewhere between 2-6% in Northen and Western Europeans Scotland has the highest proportion of redheads, as 13 percent of the population has red hair and approximately 40 percent carries the recessive redhead allele. (Ireland has the second highest percentage; as many as 10 percent of the Irish population have red, auburn, or strawberry blond hair. It is thought that up to 46 percent of the Irish population carries the recessive redhead gene. Red hair reaches frequencies of up to 10 percent in Wales.) Although the US has the largest population of redheads with at 6 to 18 million, compared to approximately 650,000 in Scotland and 420,000 in Ireland the proportions of red headedness in the Celtic nations is much higher.

Red hair is characterised by high levels of the reddish pigment pheomelanin and relatively low levels of the dark pigment eumelanin and appears in people with two copies of a recessive variant of a gene on chromosome 16 which causes a change in the MC1R protein.

Scotland is renowned for having “variable” weather (I’ll stop short of saying bloody terrible!) but what does this have to do with the higher than average percentage of redheads in Scotland? Well it seems the papers have gotten it the wrong way around slightly: bad Weather doesn’t cause hair to turn red (so you can stop cowering indoors blondes and Brunettes) rather bad weather allows redheads to survive.

Typically people with red hair also have fair skin and freckles: also due the variant MC1R gene.  It is melanin in the skin which aids UV tolerance through suntanning, but fair-skinned persons lack the levels of melanin needed to prevent UV-induced DNA-damage. Thus individuals with pale skin are highly susceptible to a variety of skin cancers such as melanoma, basal cell carcinoma, and squamous cell carcinoma. Which is why redheads are strongly advised to follow Baz Luhrmans advice and “wear sunscreen”.

If the genetics of redheadedness had evolved in the cradle of life it would have been a significant disadvantage to individuals with the associated traits: under a burning sun fair skinned redheads would blister, burn and this would seriously impact on their day to day lifes. However, Pritchard goes on to point out, redheads only started appearing around 20,000 years ago when homo sapiens reached cooler climes.

Why would this be the case?

Well as groups of humans pushed North they isolated themselves from other groups and effectively made their gene pool smaller. With a small gene pool mutation becomes more likely and it is in these smaller groups that the mutation emerged and survived due to more favourable conditions than the baking African sun. It seems likely that Britain and Ireland’s island nature may have ensured the gene became more prevalent in the population again by limiting contact with a wider continental gene pool.

All very interesting but is it science? Well as Pritchard notes the study is

“Speculation rather than scientific study, but it is plausible”.

I am inclined to agree – however the papers seem to have taken the story and ran with it – using it as an excuse to splash redheads all over their pages and make jokes about CU JIMMY hats and the Scottish weather. The Telegraph earns some plaudits for making it clear that the “research” is speculative and “non-scientific” however the Mail… well it’s the Mail so the story is pretty much indistinguishable from what one might refer to as it’s “proper science coverage”.

All in all not really a case of bad science or particularly terrible journalism – so perhaps we can step down from red alert after all.

Advertisements