Efficacy of vitamin D supplementation according to vitamin D-binding protein polymorphisms.

Objectives: The aim of this study was to determine the influence of vitamin D-binding protein (DBP) gene polymorphisms in vitamin D metabolites before and after vitamin D supplementation.

Methods: In all, 234 participants (126 women; 108 men) with vitamin D deficiency [25(OH)D <50 nmol/L] were given 50 000 IU of vitamin D supplements for 8 wk followed by daily maintenance of 1000 IU for 4 mo. Two single-nucleotide polymorphisms (rs4588 and rs7041) in DBP coding gene were assessed.