WHAT CAN GENETICS TELL US ABOUT OUR SKIN?
It’s clear that both nature and nurture play a role in skin appearance as we age. Regarding nurture (extrinsic factors), lifestyle choices around diet, fitness, sun exposure, and substance use reflect heavily on skin quality . And regarding nature (intrinsic factors), our racial background(s) determine skin and hair tone, thickness, and textures [2–4]. However, outside of melanin production, what other genetic differences contribute to skin aging and resilience to stressors? Furthermore, could a deeper understanding of our genetics lead us to personalized skin care solutions?
SINGLE NUCLEOTIDE POLYMORPHISM (SNP)
Phenotypic, or observable variability between individuals like eye color, hair color, skin tone, and even disease risk is largely explained by SNPs [5,6]. SNP is a genetics term that refers to a single change at a specific location in the DNA sequence that correlates with some sort of identifiable trait in at least 1% of the population . While some traits are visible to the naked eye, recent research has revealed that SNPs also influence our ability to produce collagen, maintain moisture content, accumulate wrinkles, and our sensitivity to certain extrinsic stressors [3,8–11]. So, how are SNPs discovered and how do we find out which ones are relevant to us?
GENOME WIDE ASSOCIATION STUDIES (GWAS)
GWAS are large, cross-sectional studies that examine the sequenced genomes of thousands to millions of participants. For example, in a study of over 26,000 individuals, researchers examined the genomes of over 3,000 acne vulgaris sufferers versus non-affected individuals. They were able to identify 15 SNPs that were statistically unique to the population of acne vulgaris sufferers . Other inquiries have identified SNPs that correlate with skin aging in both European and more melanin-rich Latin American populations . GWAS studies by large teams of skilled researchers are helping us understand how much of the skin aging process we have control over and choose the most effective therapies .
PERSONALIZED SKIN CARE
Because there are tens to hundreds of SNPs that can correlate with a specific skin phenotype, it will take a while for commercial skin care products to account for our specific genetic predispositions. In the example of acne described above, each SNP represents a possible enzyme or affected pathway that could be targeted to treat acne and further clinical research must be done to develop effective products. For those with an interest in biohacking, having your entire genome sequenced through companies like Nebula Genomics can allow you the freedom to compare your genome with the results of this preliminary literature. You may gain a better understanding of your risks of hyperpigmentation, photoaging, acne, and skin cancer. Interestingly, some SNPs associated with reduced photoaging can be traced back to specific racial backgrounds while others are relevant across different ethnicities [4,13,14]. There is much more to the genetic determinants of skin aging than melanin content and we have barely scratched the surface of this exciting skin care revolution.
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