FokI and BsmI polymorphisms of the vitamin D receptor gene and bone mineral density in a random Bulgarian population sample.

Numerous studies on vitamin D receptor (VDR) gene polymorphisms differ with conflicting data in various populations. We studied the association of FokI and BsmI polymorphisms in the gene encoding the vitamin D receptor with bone mineral density (BMD) in 219 persons of Bulgarian nationality. The calculated relative risk (RR) for low bone mineral density is higher for FokI marker (3.14) compared to BsmI marker (2.44). The etiological factor (EF), which shows association between polymorphisms investigated and illness on populational level, is defined as EF = 0.51 for FokI marker and EF = 0.42 for BsmI marker. Because of this we conclude that FokI and BsmI polymorphisms are closely related to low BMD at the forearm and lumbar spine. Both polymorphisms are useful genetic markers in determining BMD and osteoporosis risk. Further studies of larger cohorts and in ethnically diverse subgroups are necessary.