OBJECTIVETo investigate the relationship of Msp AI polymorphism in the promoter region of cytochrome P450c 17alpha (CYP17) gene with bone mass and bone size in Shanghai men of Han nationality.

METHODSThe CYP17 Msp AI genotype was determined by polymerase chain reaction-restriction fragment length polymorphism in 397 unrelated men (324 healthy men, 73 osteoporosis patients) aged 46-80 years of Han nationality in Shanghai. Bone mineral density (BMD), bone mineral content (BMC), and bone cross-section area (CSA) at lumber spine 1-4 and at any sites of proximal femur, including femoral neck, trochanter and Ward's triangle were measured by duel-energy X-ray absorptiometry.

RESULTSFrequency distributions of CYP17 genotype were TC (51.1%), CC (33.8%), and TT (15.1%). The allele frequencies T and C were 40.7% and 59.3%, respectively. Allele frequencies did not deviate from Hardy-Weinberg equilibrium. The frequencies of CYP17 Msp AI genotype did not show difference between osteoporosis cases and healthy controls. In group of all population, or in subgroups of osteoporosis patients and healthy men, CYP17 Msp AI genotype was not significantly associated with BMD, BMC, and CSA at lumber spine 1-4 and at any sites of proximal femur after having been adjusted for age, weight, and height with analysis of covariance.

CONCLUSIONMsp AI polymorphism of CYP17 gene is not a genetic factor that influence the variation of bone mass and bone size in Shanghai men of Han nationality.