Introduction: The TGFBI gene which encodes transforming growth factor beta 1, is a strong candidate for susceptibility to osteoporosis and several studies have reported associations between bone mineral density (BMD), osteoporotic fractures and polymorphisms of TGFBI, although these studies have yielded conflicting results.
Methods: We investigated associations between TGFBI polymorphisms and BMD and fracture in the GENOMOS study: a prospective multicenter Study involving 10 European research studies including a total of 28,924 participants. Genotyping was conducted for known TGFBI polymorphisms at the following sites: G(-1639) -A (G(-800) -A, rs1800468), C-1348-T (C-509-T, rs1800469), T-29-C (Leu10Pro, rs1982073), G(74)-C (Arg25Pro, rs1800471) and C-788-T (Thr263Ile, rs1800472). These polymorphisms were genotyped prospectively and methodology was standardized across research centers. Genotypes and haplotypes were related to BMD at the lumbar sine and femoral neck and fractures.
Results: There were no significant differences in either women or men at either skeletal site for any of the examined polymorphisms with the possible exception of a weak association with reduced BNID (- 12 mg/m(2)) in men with the T-1348 allele (p < 0.05). Nine of the haplotypes was associated with BMD and none of the polymorphisms or haplotypes significantly affected overall risk of fractures, however, the odds ratio for incident vertebral fracture in carriers of the rare T-788 allele was 1.64 (95% CI: 1.09-2.64), p < 0.05.
Conclusions: This study indicates that polymorphic variation in the TGFBI gene does not play a major role in regulating BMD or susceptibility to fractures. The weak associations we observed between the C-1348-T and lumbar spine BMD in men and between C-788-T and risk of incident vertebral fractures are of interest but could be chance findings and will need replication in future studies. (c) 2007 Elsevier Inc. All rights reserved.
- transforming growth factor beta 1
- bone mineral density
- bone-mineral density
- latency-associated peptide
- Japanese women
- quantitative ultrasound
- vertebral deformity
- SP1 polymorphism