Scientists made one step closer to understanding, how redheads inherit their red hair

Redheads are quite rare. Chances are, you would like to disagree, but think on a more global scale – red hair is relatively uncommon. Interestingly, scientists still don’t know all the genetics behind redheads, despite them being fairly common in UK. Now researchers at the University of Edinburgh have looked at DNA from almost 350,000 people and discovered eight genes linked to red hair.

Red hair is not just another colour of hair. Redheads typically have pale skin and are particularly vulnerable to sunlight. They also face an increased risk of certain skin diseases, including melanoma. Scientists are not even sure how red hair is inherited, but discovering 8 genes related to it sheds some light. Especially since this is the largest genetic study of hair colour to date. It already busted the long-held belief that red hair is controlled by a single gene, called MC1R – other genes are involved as well.

Previously scientists believed that people with red hair inherited two versions of the MC1R – one from their mothers and one from their fathers. However, not everyone who has both versions of this gene turns out to be a redhead. On the other hand, scientists also knew that almost every redhead had these two versions of the MC1R gene. So it was a bit of a mystery, how a person inherits the red hair. Scientists hypothesized that other genes must be involved and they finally proved it after analysing hundreds of thousands of DNA samples from UK. Europe is particularly great for this study, because Europeans happen to have the greatest variation in hair colour, which is partly why this study concerns blondes and brunettes as well.

Scientists discovered 8 previously unknown genes, related to red hair. Some of those genes are actually involved in turning MC1R on and off. Scientists say that an increasing difference in 200 genes is responsible for the gradient of colour from black through brown to blond. Some of these 200 genes are responsible for other traits, such as curly or straight texture. Professor Albert Tenesa, one of the authors of the study, said: “We are very pleased that this work has unravelled most of the genetic variation contributing to differences in hair colour among people”.

It is quite fascinating to see that scientists are so interested in such a small part of life as hair. People have different hair and that is great. But eventually studies like this could lead to measures that could help us preventing some diseases.

Source: University of Edinburgh