Positive skin colour mutation found, according to a report in ScienceDaily 14 Jan 2014 and Molecular Biology and Evolution, DOI: 10.1093/molbev/mst158. A group of scientists in Spain have studied the distribution of a mutation in a gene for skin colour, commonly found in people living in Mediterranean regions such as Spain, Portugal, Italy and Israel. The gene is named melanocortin-1 receptor (MC1R) and codes for a protein that regulates the production of melanin, the dark pigment in skin, which is increased when skin tans. The mutation is named V60L and results in light coloured skin and hair, but still allows skin to tan when exposed to strong UV light. According to ScienceDaily, “This mutation is positive for the climate of the Mediterranean region, as it facilitates the absorption of vitamin D in the winter months, in which the ultraviolet radiation is lower. In the summer months, in which the radiation is greater, the ease to darken the skin pigmentation provides a certain protection”.
The researchers found it was present in 10-20% of the population in Spain, with the highest rates in regions with lower UV radiation. However, the mutation is associated with an increased tendency to develop melanoma, a deadly skin cancer. So why hasn’t it been selected out? The researchers suggest that decreased pigment has been favoured because it enabled vitamin D absorption in the pre-reproductive phase of life at the cost of increased melanoma risk in the post-reproductive life. According to Conrado Martínez Cadenas, of Department of Medicine in the Universitat Jaume I, one of the research team, “Melanoma has been an invisible illness to natural selection; it is the price that has to be paid for the improved survival of the species in areas of the world with low solar radiation”. The researchers wrote in their report: “We, thus, provide evidence for an adaptive value of human skin depigmentation in Europe and illustrate how an adaptive process can simultaneously help to maintain a disease-risk allele”.
Editorial Comment: Anyone who has suffered a melanoma, or lost a family member or friend to this disease, would not consider this mutation to have any positive or adaptive value. However, the researchers do have a point about dark pigment interfering with the absorption of UV light in the making of Vitamin D. This is why black Africans who move to places like Canada, where there are long dark winters, need to have extra Vitamin D in their diets. However, the survival of this mutation, along with many other mutations with similar effects, reminds us that most variations in human skin colour, especially the extreme ends of the spectrum, are the result of mutations that interfere with the melanin producing system. The wide variations we see in skin colour would not have been part of God’s original creation. The original creation was very good. Therefore, the first people would have had skin that was light enough to make vitamin D, but dark enough to protect their skin cells from cancer-causing mutations.
Furthermore, the fact that people don’t get enough sunshine today is due to severe degeneration of the environment that has occurred, particularly after Noah’s Flood. In the original good world Adam and Eve could had lived outside, all year round, gotten plenty of vitamin D, and no skin cancer despite being totally naked. Since the coming of extreme seasons after Noah’s flood, many people have needed to live indoors (or in caves) for long periods of time because the weather is too cold to be outside. Industrialisation has made this worse, with those people living in gloomy industrial cities having the worst rates of vitamin D deficiency, in spite of having very pale skin. Altogether, the great variation in human skin colour, and diseases like skin cancer and vitamin D deficiency, are a constant reminder that the real history of the world, and the human race, is from good to bad to worse. Devolution, not evolution. (Ref. dermatology, nutrition, genetics)
Evidence News vol.14, No. 7
7 May 2014
Creation Research Australia