Bone mineral density and the 570A>T polymorphism of the bone morphogenetic protein 2 (BMP2) gene in patients with inflammatory bowel disease: a cross-sectional study.

Finding genetic predictors of osteoporosis and fractures in patients with inflammatory bowel disease (IBD) may provide incentives for non-pharmacological actions and so improve the long-term prognosis of the patients. We analysed the incidence of BMP2 570A>T polymorphic variants and their association with bone mineral density (BMD) and the incidence of fractures in patients with IBD. The study comprised 198 IBD patients (100 with Crohn's disease (CD), and 98 with ulcerative colitis, (UC)) and 41 healthy controls. Bone densitometric analysis was carried out using the DXA method. The 570A>T polymorphisms in the BMP2 gene were genotyped using RFLP. We found significant differences in the BMD and T-scores of the lumbar spine (L2-L4) and femoral neck between the three groups. In controls and CD patients, the highest L2-L4 BMD was found in carriers of the AA variant of the BMP2 gene, while among UC patients it was the case of TT carriers. In both femoral neck and lumbar spine among UC patients, the highest BMD was observed in carriers of the TT variant of the BMP2 gene. Among patients with CD and in the control group, the highest L2-L4 BMD was found in carriers of the AA variant, whereas in UC patients, it was the case of TT homozygotes. Within the femoral neck, there were no significant differences in BMD for the carriers of individual variants of BMP2 gene polymorphism. We conclude that the 570A>T polymorphism of the BMP2 gene, no statistically significant relationship was observed between the polymorphic variant and bone mineral density or the incidence of fractures in IBD patients.