title: IL12A, MPHOSPH9/CDK2AP1 and RGS1 are novel multiple sclerosis susceptibility loci.
abstract: A recent meta-analysis identified seven single-nucleotide polymorphisms (SNPs) with suggestive evidence of association with multiple sclerosis (MS). We report an analysis of these polymorphisms in a replication study that includes 8,085 cases and 7,777 controls. A meta-analysis across the replication collections and a joint analysis with the discovery data set were performed. The possible functional consequences of the validated susceptibility loci were explored using RNA expression data. For all of the tested SNPs, the effect observed in the replication phase involved the same allele and the same direction of effect observed in the discovery phase. Three loci exceeded genome-wide significance in the joint analysis: RGS1 (P value=3.55 x 10(-9)), IL12A (P=3.08 x 10(-8)) and MPHOSPH9/CDK2AP1 (P=3.96 x 10(-8)). The RGS1 risk allele is shared with celiac disease (CD), and the IL12A risk allele seems to be protective for celiac disease. Within the MPHOSPH9/CDK2AP1 locus, the risk allele correlates with diminished RNA expression of the cell cycle regulator CDK2AP1; this effect is seen in both lymphoblastic cell lines (P=1.18 x 10(-5)) and in peripheral blood mononuclear cells from subjects with MS (P=0.01). Thus, we report three new MS susceptibility loci, including a novel inflammatory disease locus that could affect autoreactive cell proliferation.
mesh_terms: D016022:Case-Control Studies; D002446:Celiac Disease / Q000235:genetics*; D002460:Cell Line; D049109:Cell Proliferation; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D053765:Interleukin-12 Subunit p35 / Q000235:genetics*; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D009103:Multiple Sclerosis / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D020710:RGS Proteins / Q000235:genetics*; D025521:Tumor Suppressor Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: C096151:CDK2AP1 protein, human; C508858:IL12A protein, human; D053765:Interleukin-12 Subunit p35; D020710:RGS Proteins; C080831:RGS1 protein, human; D025521:Tumor Suppressor Proteins