Association of GDF5, SMAD3 and RUNX2 polymorphisms with temporomandibular joint osteoarthritis in female Han Chinese

Temporomandibular joint osteoarthritis (TMJOA) is a complex disease and has a strong genetic component in its pathogenesis. Experimental evidence suggests the involvement of biological pathway in the disease. This case-control study was designed to investigate whether five common single nucleotide polymorphisms (SNPs) in GDF5, SMAD3, RUNX2, TGFβ1 and CHST11, respectively, are associated with TMJOA in female Han Chinese patients. A total of 240 participants were evaluated comprising 114 female patients diagnosed with TMJOA based on Research Diagnostic Criteria for Temporomandibular Disorders and 126 healthy female controls. The SNPs of the five genes in the genomic DNA were examined by sequencing, and their allelic, genotypic and carriage rate frequency distributions, as well as the triple combination of the risk genotypes, were analysed using the logistic regression model. The SNP in GDF5 or SMAD3 showed significant association with TMJOA, a relatively weak association was observed in RUNX2. In the triple combinational analysis, the risk of TMJOA grew 5·09 times in the patients with five or six risk alleles (P 0·01). This is the first study to evaluate the association of GDF5, SMAD3, RUNX2, TGFβ1 and CHST11 with TMJOA in female Han Chinese. Our study suggests that the SNPs of genes related to TGFβ family might contribute to the risk of TMJOA.