Novel Genetic Associations for Skin Aging Phenotypes and Validation of Previously Reported Skin GWAS Results

Abstract

Facial skin characteristics are complex traits determined by genetic and environmental factors. Because genetic factors continuously influenced facial skin characteristics, identifying associations between genetic variants [single-nucleotide polymorphisms (SNPs)] and facial skin characteristics may clarify genetic contributions. We previously reported a genome-wide association study (GWAS) for five skin phenotypes (wrinkles, pigmentation, moisture content, oil content, and sensitivity) conducted in 1079 subjects. In this study, face measurements and genomic data were generated for 261 samples, and significant SNPs described in previous papers were verified. We conducted a GWAS to identify additional genetic markers using the combined population of the previous study and current study samples. We identified 6 novel significant loci and 21 suggestive loci in the combined study with p-values < 5.0 × 10−8 (wrinkles: 4 SNPs; moisture content: 148 SNPs; pigmentation: 6 SNPs; sensitivity: 18 SNPs). Identifying SNPs using molecular genetic functional analysis is considered necessary for studying the mechanisms through which these genes affect the skin. We confirmed that of 23 previously identified SNPs, none were replicated. SNPs that could not be verified in a combined study may have been accidentally identified in an existing GWAS, or the samples added to this study may not have been a sufficient sample number to confirm those SNPs. The results of this study require validation in other independent population groups or larger samples. Although this study requires further research, it has the potential to contribute to the development of cosmetic-related genetic research in the future.