Some people look older than their age, while others don’t. Why is this happening? Scientists from China reported the results of a study showing the connection of a certain gene with premature aging. Due to the presence of this gene, a dark pigment is produced in the body. It is believed that the Caucasian race with white skin appeared precisely because of him. For this reason, it is necessary to consider in more detail the relationship between aging and mutations of the white inhabitants of Europe.
Many of us want to look younger than our age, because we are convinced that it is in youth, as in a mirror, that a person’s health is reflected. In fact, as has been proven by research by reputable scientists from Denmark and the UK, a person’s external age helps determine the length of his life. This is directly related to the presence of a correlation between telomere length, which is a biomolecular marker, and external age. Gerontologists, who are also called experts on aging around the world, argue that the mechanisms that determine the drastic change in appearance need to be carefully investigated. This helps to develop the latest rejuvenation techniques. But today, too little time and resources are devoted to such research.
More recently, a large-scale study was carried out by a group of Chinese, Dutch, British and German scientists who are employees of the largest scientific institutions. His goal was to find genome-wide associations to link extrinsic age to genes. In particular, this concerned the severity of facial wrinkles. To do this, the genomes of about 2000 elderly people in the UK were carefully studied. The subjects were participants in the Rotterdam Study, which is conducted to clarify the factors that cause certain disorders in older people. Approximately 8 million single nucleotide polymorphisms, or simply SNPs, were tested to determine if there was an age-related relationship.
The appearance of a snip occurs when changing nucleotides on segments of DNA or directly in a gene. In other words, it is a mutation that creates an allele, or variant of a gene. Alleles differ from each other in several snips. The latter do not have a special effect on anything, since they cannot affect the most important sections of DNA. In this case, the mutation can be beneficial or harmful, which also applies to accelerating or slowing down the aging of the skin on the face. Therefore, the question arises of finding a specific mutation. To find the necessary association in the genome, it was necessary to divide the subjects into groups to determine single nucleotide substitutions corresponding to specific groups. The formation of these groups occurred depending on the condition of the skin on the faces of the participants.
One or more snips that occur most often must be in the gene responsible for external age. Experts conducted a study on 2693 people to find snips that determined facial skin aging, changes in face shape and skin color, and the presence of wrinkles. Despite the fact that the researchers were unable to determine a clear association with wrinkles and age, it was found that single nucleotide substitutions could be found in MC1R located on the sixteenth chromosome. But if we take into account gender and age, then there is an association between the alleles of this gene. All humans have a double set of chromosomes, so there are two copies of each gene. In other words, with a normal and a mutant MC1R, a person will look older by a year, and with two mutant genes, by 2 years. It is worth noting that a gene that is considered mutated is an allele that is not capable of producing a normal protein.
To test their results, scientists used information about about 600 elderly residents of Denmark, taken from the results of an experiment whose purpose was to assess wrinkles and external age from a photo. At the same time, scientists were informed in advance about the age of the subjects. As a result, it was possible to establish an association with snips located as close as possible to the MC1R or directly inside it. This did not stop the researchers, and they decided on another experiment with the participation of 1173 Europeans. At the same time, 99% of the subjects were female. As before, age was associated with the MC1R.
The question arises: what is so remarkable about the MC1R gene? It has repeatedly been proven that it is able to encode the type 1 melanocortin receptor, which is involved in certain signaling reactions. As a result, eumelanin is produced, which is a dark pigment. Previous studies have confirmed that 80% of people with fair skin or red hair have a mutated MC1R. The presence of spins in it affects the appearance of age spots. It also turned out that skin color can, to a certain extent, influence the relationship between age and alleles. This relationship is most pronounced in those who have pale skin. The smallest association was observed in people whose skin was olive.
It is worth noting that MC1R affects the appearance of age, regardless of age spots. This indicated that the association may well be due to other facial features. The sun may also be a determining factor, since mutated alleles cause red and yellow pigments that are unable to protect the skin from ultraviolet radiation. Despite this, there is no doubt about the strength of the association. According to most researchers, MC1R is capable of interacting with other genes that are involved in oxidative and inflammatory processes. Further research is needed to uncover the molecular and biochemical mechanisms that determine skin aging.