The melanocortin 1 receptor (MC1R) gene encodes instructions for the body to produce a pigment known as melanin. Variations in this gene influence the production of melanin, and the variations are most common in people with red hair, fair skin, and freckles. Thus, this version of the gene is commonly dubbed the “ginger gene.” With less melanin, redheads are most susceptible to DNA damages caused by ultraviolet radiation from the sun.
But here’s the rub from the new study: people don’t look like the typical redhead may still be highly susceptible to sun damage and they may not know it.
This is because while true redheads carry two copies of the ginger gene, people who don’t have red hair can still inherit one copy of the ginger gene. These people are called carriers, and may have hair that range from brown to blond with an almost undetectable hint of red.
And just one copy is enough to increase sun-related mutations in by 42 percent. According to researchers, this level of DNA changes is equivalent to 21 years of sun exposure.
“It has been known for a while that a person with red hair has an increased likelihood of developing skin cancer, but this is the first time that the gene has been proven to be associated with skin cancers with more mutations,” said David Adams, joint lead researcher at the Wellcome Trust Sanger Institute.
The study pointed out that around 25 percent of people in the United Kingdom are carriers. And because they may not look like the typical pale redheads, these carriers may not be aware of how sensitive they are to sun exposure, unknowingly increasing their risks for skin cancer.
According to the Skin Cancer Foundation and BBC, skin types and cancer risks fall into 6 categories:
- Type 1 - Often burns, rarely tans. Tends to have freckles, red or fair hair, blue or green eyes
- Type 2 - Usually burns, sometimes tans. Tends to have light hair, blue or brown eyes
- Type 3 - Sometimes burns, usually tans. Tends to have brown hair and eyes
- Type 4 - Rarely burns, often tans. Tends to have dark brown eyes and hair
- Type 5 - Naturally brown skin. Often has dark brown eyes and hair
- Type 6 - Naturally black-brown skin. Usually has black-brown eyes and hair
To minimize sun damage and risks for skin cancer, doctors recommend seeking shade when the sun is at its highest, from 10am to 4pm, and to use sun protection when exposed. Protection may be long-sleeves, hat, sunglasses, and sunscreen.
Additional source: BBC News