Relationship of osteocalcin and matrix Gla protein gene polymorphisms to serum osteocalcin levels and bone mineral density in postmenopausal Korean women

Objective: To investigate the relationship of osteocalcin and matrix Gla protein (MGP) gene polymorphisms to serum osteocalcin levels, and bone mineral density (BMD) in postmenopausal Korean women. Design: The osteocalcin gene Hind III and MGP gene cytosine-adenine polymorphisms were analyzed in 267 postmenopausal Korean women. Serum osteocalcin, bone alkaline phosphatase, C-telopeptide of type I collagen, and BMD at the lumbar spine and femoral neck were measured. Results: No significant differences in BMD of the lumbar spine and femoral neck were observed across MGP genotypes, whereas a significant lower BMD at the lumbar spine (but not at the femoral neck) was observed in women with the (h) allele (lower case 'h' signifies the presence of the Hind III site) in a dose-response manner. Serum osteocalcin levels among bone turnover markers studied were significantly higher in women without the 210-bp MGP (cytosine-adenine) allele, or with the osteocalcin hh genotype. Conclusions: The osteocalcin gene Hind III polymorphism is a genetic factor that is associated with BMD of the lumbar spine in Korean women, and Gla gene polymorphisms are associated with higher osteocalcin levels.