Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: UMLS:C0011849 (diabetes)
277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To assess a possible HLA association with anti-insulin autoantibodies (IAAs) in human insulin-dependent (type I) diabetes, 51 newly diagnosed type I diabetic patients (mean age 22 +/- 8 yr) were typed for HLA-DR and HLA-DQ and studied for IAAs before exogenous insulin therapy with a competitive radioimmunoassay (normal range less than or equal to 49 nU/ml). The level of IAAs in 16 patients exceeded our upper limit of normal, and 18 had high-titer islet cell antibodies (ICAs; greater than or equal to 40 Juvenile Diabetes Foundation U). A striking association with HLA-DR4 (DQw3) in both the prevalence and the level of IAAs was found (IAA positivity in patients with DR4/4 vs. DR4 heterozygous vs. non-DR4: 90 vs. 29%, corrected [c] P less than 0.01, vs. 5%, Pc less than 0.0001; IAA positivity in patients with DR4 vs. non-DR4: 50 vs. 5%, Pc less than 0.005; IAA level in patients with DR4/4 vs. DR4 heterozygous vs. non-DR4: 111 vs. 17 nU/ml, Pc less than 0.01, vs. 20 nU/ml, Pc less than 0.0001; IAA level in patients with DR4 vs. non-DR4: 45 vs. 20 nU/ml, Pc less than 0.01). In contrast, none of the DR3+ subjects had IAAs above normal range, except in conjunction with DR4 (DR3 vs. non-DR3: 12 vs. 42%, Pc less than 0.05). However, there was no significant relationship between DR3 and IAAs after correcting for the number of DR4 alleles. No relationship was seen between age of onset, IAA level, and HLA typing in our population, and no relationship was found between ICA positivity and HLA antigens.(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes 1991 Sep
PMID:HLA-associated insulin autoantibody formation in newly diagnosed type I diabetic patients. 193 22

Finnish Type 1 (insulin-dependent) diabetic families were analysed for HLA-DQ beta-chain polymorphism using a short intron-specific probe. A simple hybridization pattern was obtained in which all fragments were associated significantly with Type 1 diabetes. The simultaneous presence of two different risk markers, the allelic 12-kilobase and 4-kilobase fragments were strongly associated with Type 1 diabetes since 50% of the patients had this combination compared with only 2% of the control subjects. The cosegregated 7.5/3.0 kilobase fragments, which were associated with HLA-DR2 and DRw6 were not detected among the diabetic patients but were present in 48% of the control subjects. Our results provide further support for the location of susceptibility determining factors in the HLA-DQ gene area. The clear-cut, simple restriction fragment length polymorphism pattern obtained here, which bears a resemblance to a two allelic system, therefore makes this method applicable for estimating the risk of Type 1 diabetes at the population level.
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PMID:HLA-DQ beta-chain restriction fragment length polymorphism as a risk marker in type 1 (insulin-dependent) diabetes mellitus: a Finnish family study. 197 16

The human leukocyte antigens (HLA) are implicated in the genetic susceptibility to a large number of diseases. Some of the diseases associated with HLA class II are related to specific amino acids or epitopes of the domain of the HLA class II molecule that is distal to the membrane. In man, selective immunoglobulin A deficiency is the most common immunodeficiency, frequently resulting in recurrent sino-pulmonary infections and gastro-intestinal disorders. Associations have been described with HLA class I, and to a lesser extent with different class II alleles, which might indicate that they share some common feature. Here we study 95 IgA-D patients and find positive associations with three DR-DQ haplotypes and a strong negative association with a fourth haplotype. Comparison of the sequences of the polymorphic amino-terminal domain of the DQ beta chain showed that the three 'susceptibility' haplotypes all had a neutral alanine or valine at position 57. The 'protective' allele had the negatively charged aspartic acid at this position (Asp57). Codon 57 of the HLA-DQ beta chain has been implicated in the susceptibility to insulin-dependent diabetes mellitus. Our data suggest that the same amino acid position could possibly also influence susceptibility and resistance to selective immunoglobulin A deficiency.
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PMID:Different amino acids at position 57 of the HLA-DQ beta chain associated with susceptibility and resistance to IgA deficiency. 197 29

Insulin-dependent (Type I) diabetes mellitus is a chronic autoimmune disease. From studies in discordant twins and multiplex families a long prediabetic period has been reported. In a population-based program started in 1983, fifteen individuals at possible risk for future Type I diabetes were followed for up to 74 months. Two individuals (13%) developed Type I diabetes. These probands were characterized by the presence of high-level cytoplasmic islet cell antibodies (ICA), complement-fixing ICA, and an impaired first-phase insulin response after intravenous glucose load. Both were homozygous for a high-risk immunogenetic marker of Type I diabetes, i.e., non-Asp at codon 57 of the HLA-DQ beta chain. In all other subjects studied, the immunogenetic marker that confers "dominant resistance", aspartic acid at codon 57, was found. On the basis of our data we conclude that a combination of assays which determine ICA, first-phase insulin release, and HLA-DQB1 polymorphisms will identify individuals with a high probability of developing Type I diabetes at the population level. Conversely, HLA haplotypes positive for aspartic acid seem to confer resistance to the disease.
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PMID:Aspartic acid at position 57 of the HLA-DQ beta chain is protective against future development of insulin-dependent (type 1) diabetes mellitus. 204 76

Insulin-dependent diabetes mellitus is characterized by the infiltration of lymphocytes into the islets of Langerhans of the pancreas (insulitis) followed by destruction of insulin-secreting beta-cells leading to overt diabetes. The best model for the disease is the non-obese diabetic (NOD) mouse. Two unusual features of the class II major histocompatibility complex (MHC) of the NOD mouse are the absence of I-E and the presence of unique I-A molecules (I-ANOD), in which aspartic acid at position 57 of the beta-chain is replaced by serine. This feature is also found in the HLA-DQ chain of many Caucasians with insulin-dependent diabetes mellitus. We have previously reported that the expression of I-E prevents the development of insulitis in NOD mouse. Here we report that the expression of I-Ak (A alpha kA beta k) in transgenic NOD mice can also prevent insulitis, and that this protection is seen not only when the I-A beta-chain has aspartic acid as residue 57, but also when this residue is serine. These results show that the single amino-acid substitution at position 57 of the I-A beta-chain from aspartic acid to serine is not sufficient for the development of the disease.
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PMID:Direct evidence for the contribution of the unique I-ANOD to the development of insulitis in non-obese diabetic mice. 197 76

CD4+ T-lymphocyte clones reactive with antigen from herpes simplex virus type 1 were established from a DQw8+ donor. One T-lymphocyte clone was able to recognize HSV antigen only when presented by antigen presenting cells expressing DQw8, and only HLA-DQ-specific mAbs could inhibit the response. Using antigen presenting cells from an extensive panel of donors whose HLA-DQ molecules and genes had been established, it could be demonstrated that alanine at residue 57 of the DQ beta chain played a critical role in presentation of herpes simplex virus--derived antigen(s) to T cells. The results are interesting, since the amino acids present at residue 57 of the DQ beta chains seems to play an important role in determining susceptibility to develop or protection against insulin-dependent diabetes mellitus.
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PMID:Antigen-specific T cells restricted by HLA-DQw8: importance of residue 57 of the DQ beta chain. 216 83

There is evidence that Type I diabetes is a genetically and environmentally determined disease. Among the genetic influences the HLA system appears to play a dominant role. HLA-DQ has been strongly implicated as the primary responsible locus by the recent discovery that position 57 in the polymorphic first domain of the DQB chain appears to be a critical residue in conferring susceptibility. DQB products which contain the negatively charged amino acid aspartate at this position are protective while those containing the neutral valine, serine or alanine are susceptibility molecules. This discovery has served to explain, in a reductionist manner, some of the previously described HLA associations seen with diabetes. However, there are clear exceptions to the position 57 hypothesis which appears to explain some, but not all, of the HLA risk associated with this disease. Evidence is accumulating that the HLA contribution to diabetes susceptibility is heterogeneous, resulting in the identification of patient subgroups. When heterogeneity, revealed by studying non-HLA genes such as Gm, T-cell receptor and interleukin, are superimposed on HLA genetic risk, further complexity is likely to arise. The definition of patient subgroups defined by genetic profiles will be required in order to study the contribution of environmental factors effectively.
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PMID:Genetic susceptibility to type I diabetes: a review. 218 58

The analysis of HLA-DQ beta nucleotide sequence polymorphism in insulin-dependent diabetes mellitus (IDDM) patients and control subjects suggests a role for the DQ beta-chain in genetic susceptibility. Sequence determination and oligonucleotide hybridization was carried out on enzymatically amplified DNA from various HLA-DR-typed individuals, including the rare class of DR2+ patients. In the analysis of DQ beta variation in DR4, DRw6, and DR2 haplotypes, a correlation was observed between the presence of the negatively charged residue Asp at position 57 and low susceptibility and the presence of an Ala (DR4), Val (DRw6), or Ser (DR2) and higher susceptibility. However, important exceptions to this pattern have been identified in the analysis of heterozygous DR1/4 IDDM patients. In these individuals, susceptibility appears to correlate with specific DR beta l alleles (Dw4) on the DR4 haplotype, rather than with the DQ beta allele (DQB3.2) that contains Ala at position 57. The DQ beta alleles found in some Chinese IDDM patients also proved discordant with the position-57 correlations. Thus, although there is a general correlation between the residue at position 57 of the DQ beta-chain and IDDM susceptibility, these data do not support the notion that Asp 57 confers complete resistance or protection to IDDM. In general, these results suggest that IDDM susceptibility is conferred by specific combinations of DQ beta and DR beta sequences.
Diabetes 1990 Jan
PMID:HLA-DQ beta sequence polymorphism and genetic susceptibility to IDDM. 221 66

The presence of an amino acid other than aspartic acid at position 57 of the HLA-DQ beta chain (non-Asp-57) is highly associated with susceptibility to insulin-dependent diabetes mellitus (IDDM), whereas an aspartic acid at this position (Asp-57) appears to confer resistance to the disease. We hypothesize that the 30-fold difference in IDDM incidence across racial groups and countries is related to variability in the frequency of these alleles. Diabetic and nondiabetic individuals were evaluated in five populations, including those at low, moderate, and high risk. HLA-DQ beta genotype distributions among the IDDM case groups were markedly different (P less than 0.001), as were those among nondiabetic controls (P less than 0.001). Non-Asp-57 alleles were significantly associated with IDDM in all areas; population-specific odds ratios for non-Asp-57 homozygotes relative to Asp-57 homozygotes ranged from 14 to 111. Relative risk information from the case-control study and population incidence data were combined to estimate genotype-specific incidence rates for the Allegheny County, PA, Caucasians. These rates were used to predict the overall incidence rates in the remaining populations, which were within the 95% confidence intervals of the actual rates established from incidence registries. These results are consistent with the hypothesis that population variation in the distribution of non-Asp-57 alleles may explain much of the geographic variation in IDDM incidence.
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PMID:Worldwide differences in the incidence of type I diabetes are associated with amino acid variation at position 57 of the HLA-DQ beta chain. 221 70

The HLA-DQ beta-chain (DQB1) genes of 72 Japanese patients with insulin-dependent diabetes mellitus (IDDM) and 85 control subjects were studied with polymerase chain-reaction (PCR) amplification and allele-specific oligonucleotide hybridization. DQW4 (DQBBlank) and DQw9 (DQB3.3) were increased in IDDM patients compared with the control subjects, and DQB1.2, DQB1.9, and DQw7 (DQB3.1) were decreased. Thirty-five (48.6%) IDDM patients had both alleles carrying an aspartic acid at position 57 of the DQ beta-chain (Asp 57), 35 (48.6%) were Asp 57/non-Asp 57 heterozygous, and 2 (2.8%) had non-Asp 57 alleles only. Of 85 control subjects, the respective values for these three genotypes were 49 (57.6%), 29 (34.1%), and 7 (8.2%), respectively. The high frequency of Asp 57 alleles in both IDDM and control subjects contrasts with data for Whites. Therefore, the Asp 57 hypothesis that the presence of an aspartic acid at position 57 of DQ beta-chain provides protection against developing IDDM is not tenable for Japanese IDDM patients. The DRB1 gene, particularly position 57 of the DR beta-chain, may contribute to IDDM susceptibility in Japanese.
Diabetes 1990 Feb
PMID:High frequency of aspartic acid at position 57 of HLA-DQ beta-chain in Japanese IDDM patients and nondiabetic subjects. 222 36


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