Association study of copy number variants in CCL3L1, FCGR3A and FCGR3B genes with risk of ankylosing spondylitis in a West Algerian population.

Numerous single nucleotide polymorphisms (SNPs) were explored in the Algerian population to evaluate associated ankylosing spondylitis (AS) genetic risk factors, but no study has identified the impact of copy number variations (CNVs). The aim of the study was to determine whether CNVs of CCL3L1, FCGR3A and FCGR3B genes were also associated with the susceptibility of AS disease in Algerian population. The data set of the current study is composed of 81 patients with AS and 119 healthy controls. All samples were genotyped by digital droplet PCR (ddPCR). Chi-square test and OR calculation were used to evaluate association between CNVs and AS and the risk associated with copy numbers (CN). In results, FCGR3A CN less than two copies (<2) was significantly increased in spondylitis patients (p = .0001, OR = 7.74 [2.32-25.74]). Additionally, FCGR3A CN < 2 copies association was present only in HLA-B27 (-) patients. We have concluded that FCGR3A deletions have an independent effect on AS regarding HLA-B27 status. This is the first study that investigated the CCL3L1 CNVs in relation to AS risk disease. It reveals that CCL3L1 and FCGR3B CNVs may not be involved in susceptibility to AS risk in the Algerian population.