There are older papers on this, but this is, I think, a bigger cohort, and it's a GWAS Genome Wide Analysis. May help to explain higher susceptibility and worse results to Covid since Covid patients have lower than average circulating Vitamin D levels.


Genetic loci associated with skin pigmentation in African Americans and their effects on vitamin D deficiency

"A recent genome-wide association study (GWAS) in African descent populations identified novel loci associated with skin pigmentation. However, how genomic variations affect skin pigmentation and how these skin pigmentation gene variants affect serum 25(OH) vitamin D variation has not been explored in African Americans (AAs). In order to further understand genetic factors that affect human skin pigmentation and serum 25(OH)D variation, we performed a GWAS for skin pigmentation with 395 AAs and a replication study with 681 AAs. Then, we tested if the identified variants are associated with serum 25(OH) D concentrations in a subset of AAs (n = 591). Skin pigmentation, Melanin Index (M-Index), was measured using a narrow-band reflectometer. Multiple regression analysis was performed to identify variants associated with M-Index and to assess their role in serum 25(OH)D variation adjusting for population stratification and relevant confounding variables. A variant near the SLC24A5 gene (rs2675345) showed the strongest signal of association with M-Index (P = 4.0 x 10−30 in the pooled dataset). Variants in SLC24A5, SLC45A2 and OCA2 together account for a large proportion of skin pigmentation variance (11%). The effects of these variants on M-Index was modified by sex (P for interaction = 0.009). However, West African Ancestry (WAA) also accounts for a large proportion of M-Index variance (23%). M-Index also varies among AAs with high WAA and high Genetic Score calculated from top variants associated with M-Index, suggesting that other unknown genomic factors related to WAA are likely contributing to skin pigmentation variation. M-Index was not associated with serum 25(OH)D concentrations, but the Genetic Score was significantly associated with vitamin D deficiency (serum 25(OH)D levels less than 12 ng/mL) (OR, 1.30; 95% CI, 1.04–1.64). The findings support the hypothesis suggesting that skin pigmentation evolved responding to increased demand for subcutaneous vitamin D synthesis in high latitude environments.Author summary

Genome-wide association and replication study for skin pigmentation was performed in African Americans, and then the implication of the skin pigmentation genes in serum vitamin D variation was assessed. A variant, rs2675345, near SLC24A5 showed the strongest associations with skin pigmentation. A Genetic Score calculated using the top variants from 3 genomic regions, SLC24A5, SLC45A2 and OCA2, and West African genomic ancestry together account for a large proportion of skin pigmentation variation. The pattern of association between the Genetic Score and skin pigmentation was different between men and women suggesting an interaction between sex and genetic variation. The Genetic Score from the same 3 skin pigmentation gene variants was also associated with severe vitamin D deficiency, defined as serum 25(OH)D levels <12 ng/mL. However, skin pigmentation and vitamin D pathway gene variants account for a small but significant proportion of serum vitamin D variation. The results suggest that genomic variations strongly control skin pigmentation and also influence serum vitamin D levels."