Showing papers on "CBLB published in 2005"
TL;DR: Gene‐gene interactions probably play substantial roles in T1D susceptibility, and evidence for a genetic interaction between the CTLA4 and CBLB genes, involved in the same biological pathway of T cell receptor signaling, was observed.
Abstract: Type 1 diabetes (T1D) is a multifactorial disease with genetic and environmental components involved. Recent studies of an animal model of T1D, the Komeda diabetes-prone rat, have demonstrated that the Casitas-B-lineage lymphoma b (cblb) gene is a major susceptibility gene in the development of diabetes and other autoimmune features of this rat. As a result of the inhibitory role of Cbl-b in T cell costimulation, dysregulation of Cbl-b may also contribute to autoimmune diseases in man. Different isoforms of Cbl-b exist; we evaluated expression levels of two known transcript variants. Constitutive expression of both isoforms was demonstrated, as well as an increased expression, after cytokine exposure, of an isoform lacking exon 16, suggesting a possible role of this variant in the pathogenesis of autoimmunity. We screened coding regions of the human CBLB gene for mutations in a panel of individuals affected with several autoimmune diseases. Eight single nucleotide polymorphisms (SNPs) were detected. One SNP in exon 12 of the CBLB gene was significantly demonstrated to be associated to T1D in a large Danish T1D family material of 480 families. Evidence for common genetic factors underlying several autoimmune diseases has come from studies of cytotoxic T lymphocyte antigen 4 (CTLA4), which encodes another negatively regulatory molecule in the immune system. Gene-gene interactions probably play substantial roles in T1D susceptibility. We performed stratification of CBLB exon 12 SNP data, according to an established CTLA4 marker, CT60, and evidence for a genetic interaction between the CTLA4 and CBLB genes, involved in the same biological pathway of T cell receptor signaling, was observed.
51 citations
TL;DR: A two-gene model of the development of type 1 diabetes in which two major susceptibility genes, Cblb and MHC, determine autoimmune reaction and tissue specificity to pancreatic beta-cells, respectively is proposed.
Abstract: Type 1 diabetes mellitus is an autoimmune disease involving both environmental and genetic factors. Genetic analyses in humans and rodents have shown that the major histocompatibility complex (MHC) is a major genetic factor and that several other genes may be involved in the development of the disease. We performed genetic analysis of type 1 diabetes in a newly established animal model, the Komeda diabetes-prone (KDP) rat, and found that most of the genetic predisposition to diabetes is accounted for by two major susceptibility genes, MHC and Iddm/kdp1. In addition, we identified a nonsense mutation in the Casitas B-lineage lymphoma b (Cblb) gene by positional cloning of Iddm/kdp1. In this paper, I review our positional cloning analysis of Iddm/kdp1 and propose a two-gene model of the development of type 1 diabetes in which two major susceptibility genes, Cblb and MHC, determine autoimmune reaction and tissue specificity to pancreatic beta-cells, respectively.
14 citations
TL;DR: It is demonstrated that the C/T polymorphism located in exon 10 of the CBLB gene is not associated with Graves' disease in children and the allelic polymorphism in patients and controls with and without DRB1*09012 were not significantly different.
Abstract: The CBLB gene functions as a negative regulator of autoimmunity. Impairment of the Cbl-b signaling pathway may contribute to human autoimmune disease. dbSNP rs2305035 is a C/T polymorphism located in exon 10 of the CBLB gene. We report an association study of this polymorphism in children with Graves' disease. The patients were 158 unrelated children (125 girls) with Graves' disease, aged 9.8 +/- 3.3 years. The controls consisted of 237 adults without a history of autoimmune disease. The C allele and phenotype frequencies of patients and controls were 247 (78.2%) vs 356 (75.1%) (OR = 1.19, p >0.05) and 151 (95.6%) vs 221 (93.2%) (OR = 1.56, p >0.05), respectively. The allelic polymorphism in patients and controls with and without DRB1*09012 were also not significantly different. This study demonstrates that the C/T polymorphism in exon 10 of the CBLB gene is not associated with Graves' disease in children.
5 citations
TL;DR: The genotype-phenotype correlation for this clinically heterogeneous disease is explored and three different defects involved in the synthesis of the active form of the cofactor adenosylcobalamin are classified.