Hypothesis about the protective role of ccr5delta32 mutations in juvenile idiopathic arthritis: fiction or reality?

It is suspected that the prevalence in different ethnic groups of HLA-genotype and of mutation CCR5delta32 - factors which alter adhesion of protein CCR5 - are the causes of different prevalence of juvenile idiopathic arthritis in different ethnic populations. Prerequisites to the fact that the mutation CCR5delta32 may have importance in determining susceptibility to the disease were the observations showing that CCR5 deletion polymorphism reveals a population and geographic diversity in addition to ethnic specificity. But reports on the role of gene deletion in the CCR5 chemokine receptor susceptibility to JIA rather contradictory. 234 DNA samples of patients with systemic JIA (soJIA) were ana-lyzed. The diagnosis was made according to the ILAR criteria. DNA was isolated using QIAamp Mini Kit (QIAGEN) according to the protocol provided. Our results didn’t reveal any differences in prevalence of mutation in patients with soJIA, in patients with soJIA + macrophage activation syndrome and in total population. Our results do not support the idea of protective role of the muta-tion CCR5delta32 against soJIA, which conclusion can be explained also by probable association of soJIA with HLA-genotype or other factors of ethnicity. At the same time, it can be considered as an additional evidence of expediency of soJIA being an original disease different from the rest of JIA group of diseases.