Genetic biomarkers for diagnosis and treatment of spondyloarthropathies in Moroccan population.

Background: The spondyloarthropathies (SpA) are inflammatory rheumatologic diseases whose pathogenesis comes from interaction between genetic and environmental factors. Methods: This is a case-control analysis that aims to explore in Moroccan population the relationship of some allelic polymorphisms of the CTLA-4 CT60, FCGR3A-158G/T SNPs and HLA-B locus with SpA disease. Eighty- four Spa patients grouped according to pain site and 95 healthy individuals from Morocco were typed by sequence-based-typing methods. Results: The CTLA-4 CT60 investigation showed a significantly increased frequency of rs11571319 A allele in male patients with sacroiliitis (p corr. =0.048, OR=2.756) and a protective role of A/G genotype in SPA patients with thoracic spine (pcorr.=0.016, OR=0.055) and peripheral joints pain (pcorr.=0.036 OR=0.068), compared to controls. Furthermore, a significant increase of A/A in rs3087243 was shown in male patients with peripheral joints pain (p = 0.035 OR = 4.45). Data from FCGR3A-158 analysis evidenced a reduction of T/T (F/F) genotype in patients with thoracic spine pain (p = 0.030, OR = 0.09) and a higher frequency of G/T (F/V) (p = 0.038 OR = 5.045) towards controls. With regard to HLA-B locus, we noticed a protective role of HLA-B*45:01 (pcorr. = 0.033,OR = 0.041) and an increased frequency of HLA-B*51 alleles (51:01, 51:02, 51:08, 51:09, 51:29) and B*52:01:01 (p = 0.041,OR = 2.714), in addition to HLA-B*27 alleles (p = 0.028, OR = 2.593) commonly associated with AS pathologies. Conclusions: Our data suggest the role of some additional CTLA-4, FCGR3A and HLA-B gene polymorphisms in SPA pathogenesis of Moroccan population, useful as new diagnostic biomarkers and targets for immunotherapy.