The Role of CD1 Gene Polymorphism in the Genetic Susceptibility to Spondyloarthropathies in the Moroccan Population and the Possible Cross-Link with Celiac Disease

Spondyloarthropathies (SpA) are a group of chronic inflammatory disorders usuallyaffecting the axial spine and asymmetrical peripheral joints. Strong evidence links genetic andenvironmental factors to SpA pathogenesis. The HLA-B27 is the most important genetic factorassociated with SpA. Nevertheless, the involvement of other HLA and non-HLA loci has beenalso reported. Some patients with SpA may also manifest features of celiac disease (CeD), thussuggesting a genetic overlap across these autoimmune diseases. Recently, CD1 glycoproteins, a classof molecules able to bind and present non peptidic antigens to T cells, aroused interest for theircontribution to the pathogenesis of CeD. Therefore, to evaluate whether functional polymorphismsof CD1A and E genes also influence susceptibility to SpA, we analyzed 86 patients from Moroccoaffected by SpA and 51 healthy controls, using direct sequencing analysis. An increase of CD1E*01/01homozygous genotype (p = 0.046) was found in SpA, compared with controls. CD1E*01/01 genotypewas associated particularly to patients with sacroiliac joints/spine/peripheral joints pain (p = 0.0068),while a decrease of CD1E*01/02 genotype was evidenced compared to controls (p = 0.0065). Resultsfrom haplotypes analysis demonstrated that CD1A*02-E*02 decreased the risk of SpA, while CD1A*02-E*01 increased risk to develop disease. Our data indicate a relationship between CD1 genes andsusceptibility to SpA in the Moroccan population and suggest the existence of shared genetic risk lociacross SpA and CeD that might be useful to explain common pathogenetic features and define noveltherapeutic strategies.