Article

Interleukin 7 receptor alpha chain (IL7R) shows allelic and functional association with multiple sclerosis.

Center for Human Genetics, Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710, USA.
Nature Genetics (Impact Factor: 29.65). 10/2007; 39(9):1083-91. DOI: 10.1038/ng2103
Source: PubMed

ABSTRACT Multiple sclerosis is a demyelinating neurodegenerative disease with a strong genetic component. Previous genetic risk studies have failed to identify consistently linked regions or genes outside of the major histocompatibility complex on chromosome 6p. We describe allelic association of a polymorphism in the gene encoding the interleukin 7 receptor alpha chain (IL7R) as a significant risk factor for multiple sclerosis in four independent family-based or case-control data sets (overall P = 2.9 x 10(-7)). Further, the likely causal SNP, rs6897932, located within the alternatively spliced exon 6 of IL7R, has a functional effect on gene expression. The SNP influences the amount of soluble and membrane-bound isoforms of the protein by putatively disrupting an exonic splicing silencer.

1 Bookmark
 · 
226 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Necrotizing meningoencephalitis (NME) affects toy and small breed dogs causing progressive, often fatal, inflammation and necrosis in the brain. Genetic risk loci for NME previously were identified in pug dogs, particularly associated with the dog leukocyte antigen (DLA) class II complex on chromosome 12, but have not been investigated in other susceptible breeds. We sought to evaluate Maltese and Chihuahua dogs, in addition to pug dogs, to identify novel or shared genetic risk factors for NME development. Genome-wide association testing of single nucleotide polymorphisms (SNPs) in Maltese dogs with NME identified 2 regions of genome-wide significance on chromosomes 4 (chr4:74522353T>A, p = 8.1×10-7) and 15 (chr15:53338796A>G, p = 1.5×10-7). Haplotype analysis and fine-mapping suggests that ILR7 and FBXW7, respectively, both important for regulation of immune system function, could be the underlying associated genes. Further evaluation of these regions and the previously identified DLA II locus across all three breeds, revealed an enrichment of nominal significant SNPs associated with chromosome 15 in pug dogs and DLA II in Maltese and Chihuahua dogs. Meta-analysis confirmed effect sizes the same direction in all three breeds for both the chromosome 15 and DLA II loci (p = 8.6×10-11 and p = 2.5×10-7, respectively). This suggests a shared genetic background exists between all breeds and confers susceptibility to NME, but effect sizes might be different among breeds. In conclusion, we identified the first genetic risk factors for NME development in the Maltese, chromosome 4 and chromosome 15, and provide evidence for a shared genetic risk between breeds associated with chromosome 15 and DLA II. Last, DLA II and IL7R both have been implicated in human inflammatory diseases of the central nervous system such as multiple sclerosis, suggesting that similar pharmacotherapeutic targets across species should be investigated.
    PLoS ONE 11/2014; 9(11):e112755. · 3.53 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background: Multiple sclerosis (MS) is a chronic inflammatory demyelinating and neurodegenerative disease of central nervous system with unknown causes. Etiology of MS involves both genetic and environment factors. The interleukin 7 receptor (IL7R) gene is a promising candidate for MS, because its involvement in the autoimmunity, regulation of the T-cell homeostasis, proliferation, and anti-apoptotic signaling. Methods: We investigated the association of the IL7R gene polymorphism rs6897932 in MS patients in a case and control study. In this case and control study participating, 127 relapsing-remitting MS (RRMS) patients (mean age: 32.25, age range: 16-57) selected according McDonald criteria, and 109 ethnically, sex and age matched healthy control (mean age: 27.44, age range: 14-63) with no personal or family history of autoimmune diseases were studied. DNA was extracted from whole blood using high pure polymerase chain reaction template preparation kit from Roch Company. Amplification refractory mutation system method was applied to define the genotyping C/T within exon 6 of the IL7R gene among individuals. Results: Evaluation of the IL7R gene polymorphism revealed that the T allele and the C/T and T/T genotypes are present in 53.5%, 42.5%, 4.0%, and 68.8%, 26.6%, 4.6% in MS patients and controls, respectively. Comparison between alleles and genotypes in the MS patients and healthy controls show significant differences (P = 0.038). Conclusion: The distribution of the rs6897932 polymorphism is significantly different in our case/control study in Khuzestan Province. This single nucleotide polymorphism causes alternative splicing in exon 6 of the IL7R gene with possible influence of the autoimmunity.
    Iranian journal of neurology. 07/2014; 13(3):168-171.
  • [Show abstract] [Hide abstract]
    ABSTRACT: T helper (TH)-cell subsets, such as TH1 and TH17, mediate inflammation in both peripheral tissues and central nervous system. Here we show that STAT5 is required for T helper-cell pathogenicity in autoimmune neuroinflammation but not in experimental colitis. Although STAT5 promotes regulatory T cell generation and immune suppression, loss of STAT5 in CD4(+) T cells resulted in diminished development of experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis. Our results showed that loss of encephalitogenic activity of STAT5-deficient autoreactive CD4(+) T cells was independent of IFN-γ or interleukin 17 (IL-17) production, but was due to the impaired expression of granulocyte-macrophage colony-stimulating factor (GM-CSF), a crucial mediator of T-cell pathogenicity. We further showed that IL-7-activated STAT5 promotes the generation of GM-CSF-producing CD4(+) T cells, which were preferentially able to induce more severe EAE than TH17 or TH1 cells. Consistent with GM-CSF-producing cells being a distinct subset of TH cells, the differentiation program of these cells was distinct from that of TH17 or TH1 cells. We further found that IL-3 was secreted in a similar pattern as GM-CSF in this subset of TH cells. In conclusion, the IL-7-STAT5 axis promotes the generation of GM-CSF/IL-3-producing TH cells. These cells display a distinct transcriptional profile and may represent a novel subset of T helper cells which we designate as TH-GM.Cell Research advance online publication 21 November 2014; doi:10.1038/cr.2014.154.
    Cell Research 11/2014; · 11.98 Impact Factor

Full-text (3 Sources)

Download
93 Downloads
Available from
May 23, 2014