Association of adiponectin gene polymorphisms with knee osteoarthritis.

Aim: To investigate the possible relationship of adiponectin () gene polymorphisms, plasma adiponectin, and the risk of knee osteoarthritis (OA).

Methods: A total of 398 subjects, 202 knee OA patients and 196 healthy individuals, were enrolled in the case-control study. Genotyping at +45T/G (rs2241766) and +276G/T (rs1501299) loci was performed using polymerase chain reaction-restriction fragment length polymorphism. Plasma adiponectin levels were assessed using enzyme-linked immunosorbent assay. OA severity was determined using the Kellgren-Lawrence (KL) grading system.

Results: No significant associations were observed in the genotype distributions and allele frequencies at two loci of +45T/G and +276G/T polymorphisms in the ADIPOQ between knee OA patients and control subjects. There was a significant association between genotype distribution of +276G/T polymorphism and KL grade 2, 3 or 4 ( = 0.037, = 0.046, = 0.016, respectively). At +45T/G locus, the percentage of GG genotype was notably greater in control subjects (13.40%) compared with OA subjects (1.70%) ( = 0.023). Plasma adiponectin was markedly decreased in OA subjects compared with control subjects ( = 0.03). Likewise, circulating adiponectin in OA subjects was notably lesser than that in control subjects in GG genotype of +45T/G ( = 0.029) and +276G/T polymorphisms ( = 0.012).

Conclusion: Polymorphisms +45T/G and +276G/T of the gene might not be responsible for OA susceptibility among Thais.