Common variants of FUT2 are associated with plasma vitamin B12 levels.
Level 3 - non-randomized controlled study
Observational cross-sectional genetic association study nested in a cohort with independent replication
PubMed 18776911 · doi:10.1038/ng.210
What was done
A genome-wide association scan (discovery cohort, n = 1,658) and an independent replication sample (n = 1,059) were evaluated among female participants from the Nurses' Health Study to identify genetic determinants of plasma vitamin B12 levels.
What was found
The rs492602 single-nucleotide polymorphism in FUT2 was strongly associated with plasma vitamin B12 concentrations (combined P = 5.36 x 10^-17). Women homozygous for the rs492602[G] allele showed higher B12 levels. This allele was in strong linkage disequilibrium with the FUT2 nonsecretor variant W143X. Absolute values and effect sizes were not reported in the abstract.
Why it matters
The study links common variation in the FUT2 gene to circulating vitamin B12 status, proposing secretor status as a potential mechanism influencing B12 absorption.
Limits
The study was restricted to female participants from the Nurses' Health Study. Absolute effect sizes, baseline B12 concentrations, dietary intake data, and functional absorption assays were not reported in the abstract.
Cited by
- supports Genetic polymorphisms can impair the processing and absorption of cyanocobalamin forms of vitamin B12.