Rs12785878

rs12785878, located near the 7-dehydrocholesterol reductase DHCR7 gene on chromosome 11q12, has been linked by several studies to vitamin D serum concentrations.

In both studies, the allele associated with lower vitamin D, and thus the potential for vitamin D insufficiency, is rs12785878(G). Carriers of two such alleles have lower vitamin D than carriers of one allele, who in turn on average have lower vitamin D levels than rs12785878(T;T) individuals.

A near-perfect proxy (i.e. substitute) for rs12785878 appears to be rs7944926.