title: Association of rs6822844 within the KIAA1109/TENR/IL2/IL21 locus with rheumatoid arthritis in the Algerian population.
abstract: Increasing evidence suggests that the rs6822844, within KIAA1109/TENR/IL2/IL21 gene cluster on 4q27, is strongly associated with rheumatoid arthritis (RA) in the Caucasian population. The aim of this study is to investigate the possible association between the SNP rs6822844 and susceptibility to RA in the Algerian Maghreb population, and to explore the association with the clinical and immunological features of RA. The polymorphism rs6822844 was genotyped in 323 RA patients and 323 healthy individuals using the TaqMan assay. A strong association of IL2/IL21 with RA susceptibility was detected in the Algerian population [odds ratio (OR) = 2.57 (95% confidence interval (CI) 1.74-3.83), P = 10(-4) ]. Our results revealed that IL2/IL21 predisposed to disease development in both autoantibody positive and negative disease. Meanwhile, the association was stronger in RA patients with anti-cyclic citrullinated peptides (ACPA) positive than those with ACPA negative [OR = 2.30 (95% CI 1.53-3.51), P = 10(-4) and OR = 1.98 (95% CI 1.01-4.22), P = 0.037, respectively]. Moreover, our findings showed a moderate association of the rs6822844 polymorphism with disease activity (P = 0.014). This study indicates for the first time that there is a strong association between IL2/IL21 rs6822844 variant and susceptibility to RA in the Algerian population, and that this association was independent from the autoantibodies status of RA patients.
authors.affiliation: Immunology Department, Beni Messous Teaching Hospital, Algiers, Algeria.|Laboratory of Cellular and Molecular Biology, Cytokine and NO Synthase Team, USTHB, Algiers, Algeria.
authors.forename: S
authors.initials: S
authors.lastname: Louahchi
authors.affiliation: Immunology Department, Beni Messous Teaching Hospital, Algiers, Algeria.
authors.forename: I
authors.initials: I
authors.lastname: Allam
authors.affiliation: Biology Department, Beni Messous Teaching hospital, Algiers, Algeria.
authors.forename: N
authors.initials: N
authors.lastname: Raaf
authors.affiliation: Immunology Department, Beni Messous Teaching Hospital, Algiers, Algeria.
authors.forename: L
authors.initials: L
authors.lastname: Berkani
authors.affiliation: Immunology Department, Beni Messous Teaching Hospital, Algiers, Algeria.
authors.forename: A
authors.initials: A
authors.lastname: Boucharef
authors.affiliation: Rheumatology Department, Ben Aknoun Specialized Center, Algiers, Algeria.
authors.forename: A
authors.initials: A
authors.lastname: Abdessemed
authors.affiliation: Rheumatology Department, Ben Aknoun Specialized Center, Algiers, Algeria.
authors.forename: N
authors.initials: N
authors.lastname: Khaldoun
authors.affiliation: Rheumatology Department, Beni Messous Teaching Hospital, Algiers, Algeria.
authors.forename: N
authors.initials: N
authors.lastname: Bahaz
authors.affiliation: Rheumatology Department, Ben Aknoun Specialized Center, Algiers, Algeria.
authors.forename: A
authors.initials: A
authors.lastname: Ladjouze-Rezig
authors.affiliation: Epidemiology Department, Beni Messous Teaching Hospital, Algiers, Algeria.
authors.forename: A
authors.initials: A
authors.lastname: Nebbab
authors.affiliation: Laboratory of Immunology, Faculty of Medicine, Algiers 1 University, Algiers, Algeria.
authors.forename: M
authors.initials: M
authors.lastname: Ghaffor
authors.affiliation: Immunology Department, Beni Messous Teaching Hospital, Algiers, Algeria.|Laboratory of Immunology, Faculty of Medicine, Algiers 1 University, Algiers, Algeria.
authors.forename: R
authors.initials: R
authors.lastname: Djidjik
mesh_terms: D000328:Adult; D000462:Algeria; D001172:Arthritis, Rheumatoid / Q000208:ethnology / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D001323:Autoantibodies / Q000096:biosynthesis / Q000235:genetics; D016022:Case-Control Studies; D002894:Chromosomes, Human, Pair 4 / Q000737:chemistry; D005006:Ethnicity; D005260:Female; D015870:Gene Expression; D056726:Genetic Association Studies; D056426:Genetic Loci; D020022:Genetic Predisposition to Disease; D020662:Guanine Nucleotide Exchange Factors / Q000235:genetics* / Q000276:immunology; D006801:Humans; D007376:Interleukin-2 / Q000235:genetics* / Q000276:immunology; D007378:Interleukins / Q000235:genetics* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D012720:Severity of Illness Index; D044465:White People; D000098546:Interleukin-21
chemical_list: D001323:Autoantibodies; D020662:Guanine Nucleotide Exchange Factors; C525068:IQSEC3 protein, human; D007376:Interleukin-2; D007378:Interleukins; D000098546:Interleukin-21
keywords: interleukin (IL)2/IL21; rheumatoid arthritis; rs6822844; susceptibility