Genetic Variation in VKORC1 and Risk for Osteoporosis

The vitamin K epoxide reductase complex subunit 1 (VKORC1) plays an important role in bone development and bone metabolism by influencing the vitamin K cycle. The aim of this study was to investigate the association between VKORC1 gene polymorphisms and bone mineral density and the risk of osteoporosis.We determined VKORC1 gene polymorphisms (rs9923231 and rs9934488) by using polymerase chain reaction-restriction and Sanger sequencing method in 606 postmenopausal women including 288 osteoporosis patients and 318 healthy controls.No significant differences were observed in the rs9934488 polymorphisms between the osteoporosis group and controls. Subgroup analyses also indicated no positive result. VKORC1 rs9923231 polymorphism increased the risk of osteoporosis in the homozygous and allelic models. A significant correlation was observed in a subgroup of the elderly (age ≥55 years). Additionally, the genotypes of the rs9923231 polymorphism were significantly associated with low body mass index, and T-score, but not with age, serum calcium, or phosphorus.In conclusion, VKORC1 rs9923231 polymorphism is a genetic contributor to osteoporosis risk and it should be confirmed in large well-designed studies.