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.

Imaging. Radiological assessment of hand OA.

OBJECTIVE: The different radiographic procedures and methods for reading films and assessing the status and progression of hand osteoarthritis (OA) were reviewed. METHODS: The methods that relate to each of the above procedures were assigned to categories upon which there was or was not general agreement. RESULTS: It was agreed that the radiographic method should use published standardized radiographic protocols; that X-ray features should be graded separately for determining the extent of the disease and that changes in osteophyte size was the most sensitive indicator of progression. For epidemiological studies films should be read blind and randomly, but for assessing progression films should be read in pairs and in sequence. No agreement was obtained on the value of the lateral radiographic view of the hand nor on which radiographic atlas would be best for long-term longitudinal studies. CONCLUSIONS: Further work was required to evaluate the role of MRI and scintigraphy in hand OA; radiographic atlases could be improved by incorporating diagrams to illustrate the change in grade for each feature; validation was required for methods of assessment in long-term trials.