Association of polymorphisms in the peroxisome proliferator-activated receptor gamma gene and osteoarthritis of the knee.

OBJECTIVES

To study the association between two common polymorphisms in the peroxisome proliferator-activated receptor gamma (PPARgamma) gene and susceptibility to, and severity of, osteoarthritis in a French-Canadian population.

METHODS

Genomic DNA was obtained from 172 patients with osteoarthritis and 210 ethnically matched healthy controls. Genotyping for the polymorphisms in the PPARgamma gene (Pro12Ala and C1431T) was carried out using polymerase chain reaction-restriction fragment length polymorphism. The standard Kellgren-Lawrence grading score and the French version of the Western Ontario and McMaster Universities Osteoarthritis Index were used to assess the radiological and functional severity of the disease. Estimated haplotypes were generated using the expectation maximisation algorithm. Genotype and allele frequencies were analysed using the chi2 test.

RESULTS

Genotype and allele frequencies for either polymorphism in the PPARgamma gene did not differ significantly between patients with osteoarthritis and controls. Moreover, no significant differences were observed after stratification of patients according to age at disease onset, radiological or functional severity. Similarly, haplotype analysis of both polymorphisms in the PPARgamma gene showed no association of any haplotype with susceptibility to, or severity of, osteoarthritis.

CONCLUSION

These findings suggest that the examined polymorphisms in the PPARgamma gene do not contribute to susceptibility to, or severity of, osteoarthritis in the French-Canadian population.