What Causes Red Hair?
Red hair is produced by mutation of MC1R gene which results in the lack of production of eumelanin. Eumalanin is skin pigmentation which darkens the skin and protects skin against the sun. Redheads have low production of eumelanin which causes pale skin, freckles and red hair. The red hair mutation is optimized for northern climates. The low eumelanin in redheads puts them at risk of sunburns and skin cancer with sun exposure but their pale skin is an advantage in the lesser sunlight of northern climates because vitamin D is better produced by pale skin which is a vital vitamin for health.
Related IFOD: How exactly does sunscreen work?
Red Hair is Quite Rare
Only about 1-2% of the human population have red hair, which is about 140 million people. The highest concentration of redheads in is Scotland where 13% of the population are redheads followed by Ireland at 10%.
Redheads are so rare because the mutated MC1R gene is recessive and thus must be carried by both parents. Thus, it is more common in remote and closed northern regions like Ireland, Scotland and Scandinavia.
Having both red hair and blue eyes is extremely rare because both are recessive traits. 1-2% of the population are redheads and about 17% have blue eyes.
Are Redheads Becoming Extinct?
Short answer: No. Over the past 15 years there have been a number of reports that redheads will go extinct because of climate change as the cloudy conditions of northern Europe potentially give way to sunnier and hotter conditions. The theory is that these climate changes will make being a redhead deadly and will thus lead to the extinction of redheads. This is silly. Being a redhead would have to be nearly toxic in order for there to be a big decline in redheads . People with red hair live all over the world without being killed by the sun like they are vampires. Here is a helpful article from Buzzfeed on this topic and another one from The Guardian debunking this theory.
Some Downsides of Being a Redhead
While extinction is not a legitimate concern, there are some drawbacks of being a redhead, including:
- Redheads feel more pain
- They are more sensitive to the cold
- They have a slightly higher risk of Parkinson’s Disease
- Redheads, and even non-redhead recessive carriers of the MC1R gene, are at a much higher risk of skin cancer
- They tend to appear slightly older than their chronological age