Objective To investigate the possible relationship between bone mineral density and polymorphism of the estrogen receptor (ER) gene in Shanghai healthy postmenopausal women Methods 250 unrelated healthy postmenopausal women were selected for bone mineral density (BMD) determination by Dual energy X ray absorptiometry (DEXA) and polymorphism of estrogen receptor gene analyses by polymerase chain reaction restriction fragment length polymorphism (PCR RFLP) Results PvuⅡ polymorphisms of ER gene was associated with low Troch BMD ( P =0 0153) while there was no significant relationship between XbaⅠ polymorphism of ER gene and BMD at any of skeletal sites included in the present study, and the combination of PvuⅡ and XbaⅠ polymorphisms of ER gene was significantly associated with both low Lumbar 2-4 ( P =0 0369) and Troch ( P =0 0384) BMD Multiple stepwise regression analysis also indicated that two combined polymorphisms were correlated significantly with Lumbar 2-4 BMD ( P =0 0254) while this correlation was not revealed at any other skeletal sites Conclusion There is significant relationship between the polymorphism of ER gene and both Lumbar 2-4 BMD and Troch BMD It is significant to explore the pathogenesis of osteoporosis and to prevent the development of osteoprosis by use of molecular genetics Objective To investigate the possible relationship between bone mineral density and polymorphism of the estrogen receptor (ER) gene in Shanghai healthy postmenopausal women Methods 250 unrelated healthy postmenopausal women were selected for bone mineral density (BMD) determination by Dual energy X ray absorptiometry (DEXA) and polymorphism of estrogen receptor gene analyzes by polymerase chain reaction restriction fragment length polymorphism (PCR RFLP) Results PvuⅡ polymorphisms of ER gene was associated with low Troch BMD (P = 0 0153) while there was no significant relationship between XbaI polymorphism of ER gene and BMD at any of the skeletal sites included in the present study, and the combination of PvuII and XbaI polymorphisms of ER gene was associated with both low Lumbar 2-4 (P = 0 0369) and Troch (P = 0 0384) BMD Multiple stepwise regression analysis also indicated that both combined polymorphisms were correlated significantly with Lumbar 2-4 BMD (P = 0 0254) while this correlation was not revealed at any other other skeletal sites Conclusion There is a significant relationship between the polymorphism of ER gene and both Lumbar 2-4 BMD and Troch BMD It is significant to explore the pathogenesis of osteoporosis and to prevent the development of osteoprosis by use of molecular genetics