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Query: UMLS:C0011849 (
diabetes
)
277,896
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
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.
...
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 highest risk for the development of type I
diabetes
resides with first-degree relatives of the diabetic proband, this risk being in the order of 2.9%, 6.6% and 4.9% for parents, siblings and children of the proband, respectively. The major genetic markers associated with the development of insulin-dependent
diabetes mellitus
(IDDM) is the possession of the HLA alleles DR3/DR4 and more recently the absence of aspartate in the 57th position on the beta-chain of the HLA DQ gene (HLA DQ beta
Asp
57 negative). The most important auto-immune marker for predicting preclinical IDDM is the presence of high titres (greater than 40 Juvenile Diabetes Foundation units) of islet cell antibodies (ICA), while the finding of insulin auto-antibodies (IAA) is a good predictive marker in children less than 5 years of age. The presence in a susceptible individual of ICA plus IAA is a better predictor of impending IDDM than the presence of either of these two markers alone. Antibodies which precipitate an islet membrane protein (MW 64K) are highly sensitive and specific markers of preclinical IDDM. The presence of 64K antibodies may well be the most important predictive marker of impending IDDM in the future. The progressive decline of the first phase of insulin secretion in response to an intravenous glucose challenge is associated with the onset of IDDM within 18 months. Of the immunotherapeutic agents at present used in clinically manifest IDDM, azathioprine has been shown to be ineffective in increasing the remission phase, while the value of nicotinamide is controversial.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Can we predict and/or prevent type I diabetes? 221 82
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
Recently it has been reported that 57th amino acid of DQ beta antigen was a non-
aspartic acid
in the most Caucasian patients with insulin-dependent
diabetes mellitus
(IDDM). Using serological analysis, HLA-DQ antigens show a strong association with IDDM rather than the HLA-DR antigens. In the Caucasian population, IDDM is associated with DQw2 and DQw3 antigens. However, in the Japanese population, DQw4 and DQw9 antigens are strongly associated with IDDM. In order to determine the possible significance of the 57th amino acid of DQ beta chain for the susceptibility to IDDM in Japanese, we performed DNA Sequence analysis of HLA-DQB from Japanese IDDM patient, its same HLA genotyped healthy sibling and B cell line with Japanese IDDM associated haplotype. The results revealed that all of the 57th amino acid are
aspartic acid
which is thought to contribute to develop IDDM resistance in Caucasian. Furthermore we could not find any other amino acid sequence of DQ beta chain which might contribute to the susceptibility of the Japanese IDDM.
...
PMID:[DNA sequence analysis of HLA-DQB genes associated with insulin-dependent diabetes mellitus in Japanese]. 222 93
Transplantation of bone marrow cells from nonobese diabetic (NOD) mice, a model for type 1 diabetes mellitus, to C3H/HeN mice, which express I-E alpha molecules and have
aspartic acid
at residue 57 of the I-A beta chain, induced insulitis followed by overt
diabetes
in the recipient C3H/HeN mice more than 40 weeks after bone marrow transplantation. When cyclosporin A, which perturbs T-cell functions, was injected intraperitoneally into [NOD----C3H/HeN] chimeric mice daily for 1 month, the chimeric mice developed insulitis and overt
diabetes
within 20 weeks following bone marrow transplantation. Transplantation of bone marrow cells from (NZW x BXSB)F1 mice, which develop lupus nephritis, myocardial infarction, and idiopathic thrombocytopenic purpura, into C3H/HeN or C57BL/6J mice induced in the recipient strains both lupus nephritis and idiopathic thrombocytopenic purpura more than 3 months after transplantation. Transplantation of a stem-cell-enriched population from (NZW x BXSB)F1 mice into normal mice also induced autoimmune disease in the recipients. These results indicate that both systemic autoimmune disease and organ-specific autoimmune disease originate from defects that reside within the stem cells; the thymus and environmental factors such as sex hormones appear to act only as accelerating factors.
...
PMID:Organ-specific and systemic autoimmune diseases originate from defects in hematopoietic stem cells. 223 44
Analysis of the frequencies of class II HLA-DR and HLA-DQ alleles by serological and DNA typing in 49 Japanese patients with type 1 (insulin-dependent)
diabetes
and 31 Japanese controls indicates the following. (i) Susceptibility is more strongly associated with the HLA-DQ subregion than with the HLA-DR subregion. (ii) Of the class II alleles detected, the A3 allele of the DQA1 locus was the most strongly associated with disease. Ninety-six percent of the patients were positive for the A3 allele compared to 53% of the controls (P = 0.001; relative risk = 19.7; confidence limits = 3.72-188.64). (iii) The DQw8 allele of the DQB1 locus, which is associated with susceptibility to type 1 diabetes in Caucasians and Blacks, was not increased in frequency in Japanese patients (22%) versus controls (19%). (iv)
Asp
-57-encoding DQB1 alleles are associated with reduced susceptibility to type 1 diabetes in Caucasians. The major predisposing haplotypes in Japanese are DR4 and DR9. By DNA sequence analysis, both of these Japanese haplotypes have
Asp
-57-encoding DQB1 alleles. Oligonucleotide dot blot analysis showed that all, except 1, of the 49 Japanese patients and all of the 31 controls have at least one
Asp
-57-encoding DQB1 allele. In addition, 40% of the patients were homozygous for
Asp
-57-encoding DQB1 alleles versus 35% of the controls. The high frequencies of
Asp
-57-encoding DQB1 alleles in this ethnic group may account for the rarity of type 1 diabetes in Japan.
...
PMID:The A3 allele of the HLA-DQA1 locus is associated with susceptibility to type 1 diabetes in Japanese. 230 May 72
Family and population studies indicate that predisposition to insulin-dependent (type I)
diabetes mellitus
(IDDM) is polygenic. It has been shown that the absence of the
aspartic acid
in position 57 (Asp57) of the DQ beta chain is positively correlated to IDDM. However, Asp57-negative haplotypes do not always confer susceptibility and conversely, some Asp57-positive haplotypes seem to be disease associated. It has been suggested that other HLA class II sequences, probably belonging to the HLA DQA1 gene, confer susceptibility to IDDM. This report, based on extensive oligonucleotide dot blot hybridization of PCR-amplified DQA1 and DQB1 genes, reinforces the importance of the Asp57-negative DQ beta chain, but also introduces the possibility that a DQ alpha chain bearing an arginine in position 52 (Arg52) confers susceptibility to IDDM. A molecular model of susceptibility to IDDM is proposed. This model strongly suggests that the disease susceptibility correlates quantitatively with the expression at the cell surface of a heterodimer, composed of a DQ alpha-chain bearing an Arg52 and a DQ beta chain lacking an Asp57. In view of the respective positions of the two residues and their charge, we might anticipate that both residues DQ beta Asp57 and DQ alpha Arg52 are critical for modulation of susceptibility, presumably via viral-antigenic peptide and/or autoantigen presentation.
...
PMID:A combination of HLA-DQ beta Asp57-negative and HLA DQ alpha Arg52 confers susceptibility to insulin-dependent diabetes mellitus. 231 83
Variations in the incidence rate of Type 1 (insulin-dependent)
diabetes mellitus
might relate to ethnic-specific genetic backgrounds. HLA-DQB 1 alleles were typed in 75 French diabetic children and 85 matched control children. Enzymatically-amplified DQB 1 exon 2 was hybridized with oligoprobes specific for the six most common alleles. Alleles coding for an
Asp
residue at position 57 in the DQ beta chain are strongly negatively associated with Type 1
diabetes
in the French population. Nevertheless, one of the diabetic children was an
Asp
57 homozygote (DQB 1.2/3.1). Among alleles coding for a residue other than
Asp
at position 57, alleles 3.2 and 2 (Ala 57) are positively associated with
diabetes
but not allele 1.1 (Val 57) which is less frequent in diabetic children than in control children. Heterozygosity for 2/3.2 alleles is the genotype most strongly associated with
diabetes
(Odds ratio = 52.9). Large comparative population studies will be necessary to determine whether the frequency of DQB 1 alleles positively associated with Type 1
diabetes
(2 and 3.2) in a given ethnicity is related to its incidence rate in the same population.
...
PMID:HLA-DQB 1 codon 57 and genetic susceptibility to type 1 (insulin-dependent) diabetes mellitus in French children. 232 49
There is evidence that certain alleles at the HLA-DQ locus are correlated with susceptibility to insulin-dependent
diabetes mellitus
(IDDM) and in particular that DQ beta-chain alleles containing
aspartic acid
at position 57 are protective. The availability of a large group of patients with IDDM enabled us to assess the role of HLA-DQ alleles in susceptibility to the disease in order to confirm and extend recent observations derived from studies of smaller numbers of patients. Using allele-specific oligonucleotide probes and the polymerase chain reaction, we studied 266 unrelated patients with IDDM and 203 unrelated normal subjects for eight HLA-DQ beta-chain alleles. Two major findings emerged from these studies. First, the presence of an HLA-DQw1.2 allele was protective. Only 6 of the 266 patients with IDDM (2.3 percent) were positive for HLA-DQw1.2, as compared with 74 of the 203 normal subjects (36.4 percent; P less than 0.001). Thus, persons with the HLA-DQw1.2 allele, which is one of the polymorphic forms of the beta chain of the HLA-DQ molecule, rarely had IDDM, no matter which other HLA-DQ beta-chain allele they inherited ("dominant protection"). Second, the presence of the HLA-DQw8 allele increased the risk of IDDM. The relative risk of IDDM was 5.6 in persons homozygous for HLA-DQw8, and it was similar in persons with the HLA-DQw1.1/DQw8 or HLA-DQw2/DQw8 haplotype ("dominant susceptibility"). However, the relative risk of IDDM in persons who had the HLA-DQw1.2/DQw8 haplotype was 0.37, demonstrating that the protective effect of HLA-DQw1.2 predominated over the effect of HLA-DQw8. We conclude that the presence of the HLA Class II antigen DQw1.2 is strongly protective against the development of IDDM, and that complete HLA-DQ typing is necessary for accurate assessment of susceptibility to IDDM.
...
PMID:Analysis of HLA-DQ genotypes and susceptibility in insulin-dependent diabetes mellitus. 234 40
HLA DQ beta chain, in particular amino acid at position 57, has been reported to contribute to susceptibility and resistance to Type 1 (insulin-dependent)
diabetes mellitus
in Caucasians. Resistance has been proposed to be conferred by
aspartic acid
at this position. To ascertain the association of HLA DQ beta and DR beta genes with Type 1
diabetes
in Japanese subjects, ten Japanese Type 1 diabetic patients were investigated at DNA level. Genomic DNA was amplified by polymerase chain reaction, and dot blot analysis was carried out using the amplified DNA with allele specific oligonucleotide probes. All patients had
aspartic acid
at position 57 of at least one of their two DQ beta chains, and there was no significant difference of amino acids at the same position of DR beta chain in patients compared to control subjects. These data indicate that the protective role of
aspartic acid
at position 57 of DQ beta chain is less significant in Japanese compared with Caucasian subjects.
...
PMID:Aspartic acid at position 57 of DQ beta chain does not protect against type 1 (insulin-dependent) diabetes mellitus in Japanese subjects. 251 91
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