Genome wide association study to identify SNPs associated with Homocysteine, Vitamin B12 and holotranscobalamin in Indian Population.

Background Vitamin B12, a cofactor for the enzyme methionine synthase, catalyzes the remethylation of homocysteine to methionine. About 50-60% of the Indian population are deficient in vitamin B12, a micronutrient that is only synthesized by microorganisms while mammals have evolved ways for its absorption from diet. Of the various factors involved in Vitamin B12 absorption, Transcobalamin II (TC II) is most important as vitamin B12 bound to TCII is bioavailable. Thus, the objective of our study was to identify the genetic variants that are associated with homocysteine, vitamin B12 and holotranscobalamin levels.