Introduction and hypothesis: Genetic studies of osteoporosis have focused on analysing single polymorphisms in individual genes - with inconclusive results. An alternative approach may involve haplotypes and gene-gene interactions. The aim of the study was to test the association between the COL1A1, ESR1, VDR and TGFB1 polymorphisms or haplotypes and bone mineral density (BMD) in Spanish postmenopausal women. Methods: Sixteen polymorphisms were analysed in 719 postmenopausal women. ANOVA, ANCOVA and Xi2 tests were used to perform the statistical analysis. Results: COL1A1 -1997G > T (p = 0.04) and TGFB1 Leu10Pro (p = 0.02) were found to be associated with adjusted lumbar spine (LS) BMD. Interactions were observed between: the COL1A1 -1997 G/T and Sp1 polymorphisms (p < 0.01 for LS BMD) and the COL1A1 -1663 indelT and VDR ApaI polymorphisms (p < 0.01 for femoral neck (FN) BMD). The COL1A1 GDs and ESR1 LPX haplotypes were associated with FN BMD (p = 0.03 and p = 0.03). Conclusions: Polymorphisms at COL1A1 and TGFB1 and haplotypes at COL1A1 and ESR1 were found to be associated with BMD in a cohort of postmenopausal Spanish women. Moreover, COL1A1 polymorphisms showed significant interactions among them and with the VDR 3′ polymorphisms. © 2006 International Osteoporosis Foundation and National Osteoporosis Foundation.
- Association studies