Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011854 (type 1 diabetes)
 20,749 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The mechanism of pancreatic B-cell destruction in type I (insulin-dependent) diabetes (IDDM) involves autoimmune phenomena based on genetic predisposition. The mechanism of action of the susceptibility genes is probably related to the function of the HLA molecules in the immune response. The genetic susceptibility is distinguished by increased frequency of the HLA antigens DR3 and DR4 and particularly their heterozygous combination DR3/DR4. Recent advances in molecular biology have resulted in a more precise definition of the genetic variants and corresponding amino acid sequences associated with IDDM. These markers may identify subjects at risk of developing the disease. However, the signs of islet-specific autoimmunity, e.g. islet-cell antibodies, which may be detected several years before the clinical onset of IDDM, are of greater predictive value. These and other arguments in favour of an autoimmune pathogenesis of type I diabetes have made preventive immunotherapy a goal for the future.
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PMID:[The role of genetic and immunological factors in the etiology of insulin-dependent diabetes]. 240 78

The DQw3.2 specificity has previously been recognized using genomic RFLP analysis and certain combinations of monoclonal antibodies. Here we report three CD4+ T lymphocyte clones (TLCs) generated from a DR3,4; DQw2,w3.1 responder stimulated with cells from a DR3,4; DQw2,w3.2 donor, and using a modified cloning procedure involving enrichment of IL-2 receptor-positive T cell during priming. The resulting TLCs were strongly inhibited by some monoclonal anti-DQ, but not anti-DR or -DP antibodies. In panel studies using HLA homozygous stimulating cells, it was found that the TLCs recognize an HLA epitope encoded by a DQ gene carried only by DR4,DQw3.2 haplotypes. By comparison with published DQ chain amino acid sequences of some stimulating cells able or not to induce a response in these clones, evidence was obtained that Ala at position 57 on the DQ beta chain is most probably involved in the epitope. The epitope is present on cells from 12 out of 12 DR4,DQw3 insulin dependent diabetes mellitus (IDDM) patients, but on cells only from 6 out of 12 healthy DR4,DQw3 controls. Thus, a DQ-encoded epitope involving residue 57 on the DQ beta chain, and which is strongly associated to IDDM, may be recognized by T cells.
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PMID:T lymphocyte clones recognizing an HLA-DQw3.2-associated epitope involving residue 57 on the DQ beta chain. 245 88

The prevalence rate for autoimmune thyroid disease (ATD) is about 30 times higher in the type I diabetic (IDDM) families that were ascertained for Genetic Analysis Workshop 5 (GAW5) than in the general population. Two approaches were used to study the clustering of ATD and IDDM in these families: 1) HLA haplotype sharing in sib pairs in which one has IDDM and the other has ATD was analyzed with the genetic interrelationship method. The hypotheses of different alleles (at the same locus or at different loci) were rejected. Thus there must exist at least one common allele that predisposes to both IDDM and ATD. 2) The DR genotype frequencies suggest that in the GAW5 families two alleles may be predisposing to ATD; a recessive DR3-associated allele and a dominant DR4-associated allele.
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PMID:Autoimmune thyroid disease in type I diabetic families. 249

Models for IDDM susceptibility based on single amino acid substitutions in class II histocompatibility genes are attractive in simplicity but are largely inconsistent with genetic epidemiological data. A simple correlation between IDDM and residue 57 of the DQ beta chain does not hold in Oriental IDDM patients, cannot account for DR3,DR4 synergism and does not explain different modes of inheritance of DR3- and DR4-related IDDM determinants. Residue 70/DR beta correlates equally well, if not better, with IDDM than does residue 57/DQ beta, but IDDM genotype distributions are compatible with multi-locus involvement of DR beta and DQ beta genes.
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PMID:Class II histocompatibility genes and insulin-dependent diabetes mellitus. 251 13

The case of a 40 year-old woman with insulin dependent diabetes mellitus associated with relapsing polychondritis, Hashimoto's thyroiditis and pituitary adrenocortical insufficiency in succession, considered as polyglandular autoimmune syndrome type III, is described. The results of this study suggest that relapsing polychondritis and pituitary adrenocortical insufficiency might be included in polyglandular autoimmune syndrome. It is very interesting that in the pathogenicity of polyglandular autoimmune syndrome type III, the elevation of OKT4/OKT8 ratio which indicates the hypofunction of suppressor T cell is shown and that she has HLA DR4 which has a significant relationship with insulin dependent diabetes mellitus in Japanese.
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PMID:A case of insulin dependent diabetes mellitus associated with relapsing polychondritis, Hashimoto's thyroiditis and pituitary adrenocortical insufficiency in succession. 252 4

Almost all human leukocyte antigen (HLA) haplotypes positive for HLA-DR4 also carry the DQw3 specificity, which appears in one of two allelic forms, DQw3.1 or DQw3.2. Previous studies have shown that the frequency of the HLA DR4-DQw3.2 allele is approximately 95% among DR4-positive haplotypes of insulin-dependent diabetics (IDDM), but only 70% in DR4-positive haplotypes of unaffected individuals. Because this difference could be due to ethnic heterogeneity, it is important to establish whether the frequency of the DQw3.2 allele is also increased when haplotypes of diabetics are compared to those of "matched" unaffected individuals, as can be done within families. We have used the Genetic Analysis Workshop 5 (GAW5) data for this purpose. In every family, each parental DR4-bearing haplotype was categorized as "IDDM" if it appeared in any affected parent or offspring, or as "control" if not. When this was done, the frequencies of the DQw3.2 and 3.1 allele in 80 IDDM haplotypes were 94% and 6% respectively but 67% and 33% in 15 control haplotypes. This difference between the two kinds of haplotypes is highly significant (P less than 0.005).
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PMID:HLA DR4-DQw3.1 and 3.2 haplotypes among insulin-dependent diabetics and their unaffected sibs in the GAW5 data. 256 53

Class II antigen genes encoded by the major histocompatibility complex region (HLA-D region) in man play an important role in susceptibility to insulin dependent diabetes mellitus (IDDM). Evidence suggests that the DQ subregion within the HLA-D region is more directly responsible for susceptibility to IDDM. Therefore, we designed a synthetic oligonucleotide specific for the DQ beta gene to further the understanding of the disease association with HLA-D region genes at the molecular level. Restriction fragment length polymorphism (RFLP) analysis was carried out using DNA isolated from nine families, each including at least two affected siblings (a total of 37 siblings). The segregation pattern of hybridizing fragments showed that: (1) for each of the DR2, DR3, and DR4 specificities, two different alleles can be identified by the DQ beta probe; (2) a 1.9 kb-Taq 1 fragment with the DR4 specificity and a 6.0 kb-Taq-1 fragment within the DR2 specificity tend to cosegregate with IDDM; (3) there was no preferential segregation of the two alleles detected within the DR3 specificity (one allele identified by a 4.7 kb-Taq 1 fragment is quite common among individuals with the DR3 specificity). The results from this study add to the evidence that certain DQ alleles appear to be more directly associated with the diabetogenic gene (or genes) in certain DR specificities.
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PMID:Application of synthetic oligonucleotides to detect DQ beta genes transmission within insulin-dependent diabetes families. 257 47

The majority of the genetic component in insulin dependent (Type 1) diabetes mellitus can be explained by associations with genes on short arm of chromosome 6 located in the major histocompatibility complex. With the advent of cloning of the HLA Class II region genes it has been possible to refine the previous known association of HLA-DR3 and DR4 with this disease. Strong associations of IDDM have now been shown to exist with the DQB1 gene and/or linked genes, although this does not completely explain the HLA susceptibility to this disease.
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PMID:The major histocompatibility complex and insulin dependent (type 1) diabetes. 257 93

The genetic association between HLA-system and chronic lymphocytic thyroiditis (CLT) related or not to type I diabetes mellitus (IDDM), have been analysed in three groups of children: 16 with CLT, 9 with CLT and IDDM, 11 with IDDM and 200 normal controls. The DQw1 antigen (75% vs 55%) was found associated with CLT, furthermore the observed increase of DR1 and DR2 antigens (37% respectively) is secondary to the linkage disequilibrium that exists between them and DQw1. DR3 antigen (60%) was found significantly increased (p less than 0.001) in CLT patients compared with the control group (24%). In diabetic patients, DR3 and DR4 were found in 85% and 63% respectively (p less than 0.001). The DR3 associated haplotype in CLT patients was different from the diabetic one's. All the diabetics, but one, were DR3-B18 haplotype carriers, but this association was only found in 25% CLT patients. The titre of thyroid microsomal antibodies (MCHA) was more frequent in the patients with DQw1 antigen (MCHA DQw1+ : 1/1072; DQw1- : 1/606). The CLT predisposition in childhood may be influenced by genes located within the HLA-region probably more than one, different from the genes related to IDDM. One of this genes closed to the HLA-DQ region, will be involved in the production of autoantibodies.
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PMID:[Susceptibility to chronic HLA-system-associated lymphocytic thyroiditis. Its relationship with insulin-dependent diabetes mellitus]. 262 85

Hyperglycemia and other metabolic derangements resulting from absolute or functional deficiency of insulin are accompanied by typical signs and symptoms of diabetes. The clinical signs and the findings of hyperglycemia over 200 mg/dl should establish a diagnosis of diabetes mellitus. An oral glucose tolerance test (O-GTT) is rarely necessary for diagnosis of diabetes in a child. A small proportion of children, however, present less severe symptoms, and may require an O-GTT. Approximately 14% of IDDM children were in coma at diagnosis in Tokyo, and 11 onset deaths (0.94%) were observed among the 1172 newly diagnosed IDDM cases in Japan. A significant decline in the onset mortality, however, has been observed in the past 20 years in Japan in association with the improvement of early management of childhood diabetes. The clinical distinction of IDDM from NIDDM is often difficult in diabetic children of Oriental origin without obesity. Japanese IDDM can be divided into two forms, abrupt and slow onset forms, but they may be essentially the same disease. There was no difference in the frequency of being tested positive for circulating ICA between the two groups of the patients. But a difference in the frequency of HLA DR4 and DRW9 was noticed between the two groups. Clinical features of 107 children with NIDDM were studied and about 75% of these cases were obese. All of them can be detected by routine urinalysis for glucose. Diet and exercise therapy in most of the newly diagnosed patients resulted in remission but some of them may require insulin or an oral hypoglycemic agent to get better glycemic control.
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PMID:Initial signs and diagnosis of diabetes--special considerations of Oriental patients. 263 91


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