Common genetic variant of GC associated with vitamin D deficiency in a Chinese population in the Netherlands

Background Genome-wide association studies among European populations have identified four single nucleotide polymorphisms (SNPs) in genes involved in vitamin D transport and metabolism affecting 25-hydroxyvitamin D [25(OH)D] concentration: rs2282679 in GC, rs6013897 near CYP24A1, rs10741657 near CYP2R1, and rs12785878 near DHCR7. It is, however, unknown whether the association with 25(OH)D can also be observed in a Chinese population living in the Netherlands. Methods Observational study. Analyses were performed under an additive (univariate and multivariate) and genotypic model using logistic regression. Results The C allele (minor allele frequency 0.28) of rs2282679 in GC was associated with vitamin D deficiency as defined by the Health Council of the Netherlands: 25(OH)D <30 nmol/l (or <50 nmol/l for persons aged ≥70 years). Univariate and multivariate odds ratios, 1.52 (95% CI 1.03, 2.24) and 1.57 (95% CI 1.04, 2.39), respectively, were not significant after Bonferroni correction. However, after extending the data by a meta-analysis, a significant association between C allele of rs2282679 and vitamin D deficiency (< 50 nmol/l) was observed (odds ratio 1.33; 95% CI 1.16, 1.52). Conclusion Our findings suggest that, apart from sun exposure, lifestyle, and environmental factors, a common variant of GC may be associated with vitamin D deficiency.