Replication Study Confirms the Association of the Common rs1800629 Variant of the TNFα Gene with Postmenopausal Osteoporosis Susceptibility in the Han Chinese Population.

BACKGROUND: Previous studies have suggested that tumor necrosis factor α (TNF-α), encoded by the TNFα gene, can increase osteoclast formation, and that specific alleles of the TNFα gene are associated with postmenopausal osteoporosis susceptibility in some populations; however, the exact molecular mechanism remains unknown.

AIMS: To investigate the potential association of nineteen polymorphisms of the TNFα gene with postmenopausal osteoporosis and bone mineral density (BMD) traits in a sample of 1288 postmenopausal women from the Han Chinese population.

METHODS: A total of 437 postmenopausal osteoporosis patients and 851 unrelated age-matched healthy women were recruited to the study. Single marker and haplotype based analyses were conducted to evaluate the association of nineteen single nucleotide polymorphisms (SNPs) in both patient and control groups.

RESULTS: The SNP rs1800629 was identified as being highly significantly associated with postmenopausal osteoporosis after accounting for age and body mass index (p = 0.000087). In addition, the GG genotype of this SNP was associated with significantly lower measures of femoral neck BMD and lumbar spine BMD. Moreover, haplotype based analyses suggested significant association signals between the haplotype block, including rs1800629 with postmenopausal osteoporosis (p < 0.001).

CONCLUSION: We have shown that a TNFα gene polymorphism, rs1800629, is highly significantly associated with postmenopausal osteoporosis and BMD in the female Han Chinese population. Additional sequencing-based studies are needed to investigate the genetic architecture of this genomic region and its relationship with osteoporosis-related phenotypes.