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)

Although HLA-DQB1 alleles encoding aspartic acid at position 57 (Asp-57) are protective against Type 1 (insulin-dependent) diabetes mellitus in Caucasians, most Japanese Type 1 diabetic patients carry at least one Asp-57 DQB1 allele. We analysed the DRB1, DQA1 and DQB1 genes of 99 Japanese patients and 86 control subjects with polymerase chain reaction and sequence-specific oligonucleotide hybridization. We found that (1) the DQA1*0301 allele was significantly increased in Type 1 diabetic patients (RR7.8, pc less than 0.0001); (2) the DRB1*0405 (Dw15) allele, which is a subtype of DR4 haplotype, was significantly increased in DR4-positive patients (RR 12.0, pc less than 0.001); and (3) although the DRw8-DQw8 haplotype was positively associated with Type 1 diabetes, the DRB1*0406-DQw8 haplotype was decreased in the diabetic patients. These data indicate that DRB1 and DQA1 genes also confer susceptibility to Type 1 diabetes in Japanese.
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PMID:Genetic analysis of HLA class II alleles and susceptibility to type 1 (insulin-dependent) diabetes mellitus in Japanese subjects. 152 22

Lack of an aspartic acid 57 in the HLA-DQ beta chain was introduced as a genetic marker of insulin-dependent diabetes mellitus (IDDM). Because 25% of the control population carries the same marker, we analyzed the DQ locus for the presence of more specific disease susceptibility markers, taking into account a possible role for the polymorphic DQA gene. We thereby identified the DQA3-DQB3.2/DQA4.1-DQB2 (DQA1*0301-DQB1*0302/DQA1*0501-DQB1*0201) genotype which was detected in 30% of the 268 typed IDDM patients and only in 1% of the 331 typed healthy controls, resulting in a relative risk of 35. This genetic marker was more frequent in patients with clinical onset before age 18 years (36%) than in patients diagnosed between age 18 and 40 years (22%) and was not observed in patients with non-IDDM. The new susceptibility genotype DQA3-DQB3.2/DQA4.1-DQB2 (DQA1*0301-DQB1*0302/DQA1*0501-DQB1*0201) may explain the well-known excess of DR3/DR4 heterozygous IDDM patients and is expected to help identify individuals at risk for developing the disease.
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PMID:Complementation of HLA-DQA and -DQB genes confers susceptibility and protection to insulin-dependent diabetes mellitus. 154 46

Glucose tolerance has been assessed in cystic fibrosis (CF) children using HbA1C and plasma glucose and insulin determinations during an oral glucose tolerance test (OGTT), along with the determination of HLA-DR and islet-cell (ICA) and anti-insulin (IAA) antibodies. Of 49 patients (25 males, 24 females), aged 2 to 21 years (mean = 10.9 years), 29 had normal glucose tolerance (WHO criteria) during OGTT, 14 had impaired glucose tolerance (IGT) and 6 had an isolated hyperglycemia at 120 min. Fasting plasma glucose and HbA1C were significantly higher in IGT than in normoglycemic patients. However, these two parameters showed poor individual predictive value of disturbance in glucose tolerance. Of 14 patients with abnormal OGTT, 7 were aged below 10 years, with 2 as young as 5 years; 8 patients were females. HLA antigens characteristic of type I diabetes tended to be found less frequently in CF patients than in the general population: 9% were DR3, 7% were DR4 and none was DR3/DR4. There were no HLA differences according to glucose tolerance. ICA and IAA were respectively detected in only one patient. Stimulated plasma insulin was low but did not correlate with glucose tolerance. In conclusion, impaired glucose tolerance is common in cystic fibrosis and can be found early in life. Although insulin secretion is decreased in this population, it does not seem to be the only factor responsible for impaired glucose intolerance. The absence of the genetical and immunological characteristics of type I diabetes confirms that glucose intolerance in cystic fibrosis is due to other pathogenetic mechanisms.
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PMID:[Research of factors for glucose intolerance in mucoviscidosis]. 155 Apr 46

Insulin-dependent diabetes mellitus (IDDM) in whites is strongly associated with particular HLA-DQ alpha beta heterodimers composed of a DQ alpha chain with an arginine at residue 52 (Arg52+) combined to a DQ beta chain lacking an aspartic acid at residue 57 (Asp57-). With the aim of confirming this association, clarifying which heterodimers account for the highest risk of IDDM and explaining the excess risk of DR3-DQw2/DR4-DQw8, 115 unrelated white IDDM patients and 108 unrelated healthy nondiabetic control subjects were studied. With polymerase chain reaction and sequence-specific oligonucleotide probes, both patients and control subjects were typed for their HLA-DQA1 and DQB1 alleles and their DQA1-DQB1 haplotype and genotype frequencies were compared. Four major findings emerged from our analysis. 1) Arg52+ DQ alpha/Asp57- DQ beta heterodimers, formed in cis and/or in trans, are strongly associated with susceptibility to IDDM; 97% of patients and 46% of control subjects had at least one such susceptibility heterodimer (relative risk [RR] 32, confidence interval [Cl] 14.25-71.86, P less than 10(-7). 2) The degree of disease susceptibility depends on the number of such DQ heterodimers that a subject can express according to his or her DQA1-DQB1 genotype. The highest RR was observed in patients with four susceptibility DQ heterodimers (RR 41, Cl 17.05-95.9). 3) Only part of the susceptibility DQ heterodimers were significantly increased in patients, conferring IDDM susceptibility of different strength. The strongest association was with the DQA1*0501-DQB1*0302 combination formed in trans position (RR 35.2, CI 12.88-96.78, P less than 10(-7).(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes 1992 Mar
PMID:Dose effect of cis- and trans-encoded HLA-DQ alpha beta heterodimers in IDDM susceptibility. 155 98

HLA-A, B, C, DR and DQ typing was performed in 381 Italian insulin-dependent diabetic patients and in 905 normal Italian subjects. The diabetic patients had significantly higher frequencies of HLA-Cw7, B8, B18, DR3, DR4, DQw2 and DQw3 and significantly lower frequencies of HLA-B17, Bw51, DR2, DR7 and DRw11. The frequency of heterozygosity for HLA-DR3/DR4 was significantly higher in patients who developed the disease in the first 2 years of life and DR3+/DR4-, DQw2 and DQw3 alleles were higher in those aged less than 14 years at onset. The HLA-DR4 allele was associated with onset of diabetes in autumn and HLA-B18 with onset in Autumn-winter. Diabetic children who were breast fed had a later onset of insulin-dependent diabetes mellitus than those who were bottle fed but these differences were independent of HLA typing (11.8 +/- 0.72 years vs 9.23 +/- 0.42 years; mean +/- SEM). We conclude that: (1) in general, HLA distribution in Italian insulin-dependent diabetic patients reflects previous data reported in other European and North American populations; (2) HLA-DR3 and DR4 are strongly associated with insulin-dependent diabetes in Italy as well, and these alleles seem to predispose to an earlier onset of the disease; and (3) breast feeding may delay the onset of the disease.
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PMID:HLA-antigens in Italian type 1 diabetic patients: role of DR3/DR4 antigens and breast feeding in the onset of the disease. 157 60

It has been suggested that HLA-DR4 is a marker of genetic predisposition to proliferative retinopathy. To investigate this relationship and potential associations between other polymorphic genes and proliferative retinopathy, a sample (n = 428) of participants in the population-based Wisconsin Epidemiologic Study of Diabetic Retinopathy was selected for typing for HLA-A, -B, -C, and -DR and a panel of other polymorphic genes. The presence of proliferative retinopathy was determined from grading of stereoscopic color fundus photographs taken at 2 examinations, 4 yr apart. In logistic regression models with repeated measures, persons with HLA-DR4 who were negative for DR3 were five times more likely to have proliferative retinopathy than those negative for both antigens after adjusting for other potential risk factors (Odds ratio = 5.43, 95% Confidence Interval (Cl) = 1.04, 28.30). HLA-C2, AK-2, and MNSs-S also were associated positively with proliferative retinopathy, and HLA-DR8 was associated inversely with this complication of diabetes in each case before adjusting for the number of comparisons. These data suggest that the genetically determined immunopathic mechanisms leading to diabetes, and in linkage disequilibrium with DR4, may independently contribute to the development of proliferative retinopathy.
Diabetes 1992 Jul
PMID:Genetic marker associations with proliferative retinopathy in persons diagnosed with diabetes before 30 yr of age. 161 3

A prospective study of a normal childhood population identified 44 islet cell antibody positive individuals. These subjects were typed for HLA DR and DQ alleles and investigated for the presence of antibodies to the M(r) 64,000 (64K) islet cell antigen, complement-fixing islet cell antibodies and radiobinding insulin autoantibodies to determine their potency in detecting subjects with impaired Beta-cell function. At initial testing 64K antibodies were found in six of 44 islet cell antibody positive subjects (13.6%). The same sera were also positive for complement-fixing islet cell antibodies and five of them had insulin autoantibodies. During the follow-up at 18 months, islet cell antibodies remained detectable in 50% of the subjects studied. In all six cases who were originally positive, 64K antibodies were persistently detectable, whereas complement-fixing islet cell antibodies became negative in two of six and insulin autoantibodies in one of five individuals. HLA DR4 (p less than 0.005) and absence of asparic acid (Asp) at position 57 of the HLA DQ beta chain (p less than 0.05) were significantly increased in subjects with 64K antibodies compared with control subjects. Of 40 individuals tested in the intravenous glucose tolerance test, three had a first phase insulin response below the first percentile of normal control subjects. Two children developed Type 1 (insulin-dependent) diabetes mellitus after 18 and 26 months, respectively. Each of these subjects was non-Asp homozygous and had persistent islet cell and 64K antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Antibodies to the M(r) 64,000 (64K) protein in islet cell antibody positive non-diabetic individuals indicate high risk for impaired beta-cell function. 161 28

Susceptibility to IDDM is strongly associated with HLA. Some HLA allelic combinations (haplotypes) can be found in most patients, whereas other haplotypes are encountered only rarely. It has been proposed that this difference in susceptibility depends on the absence (in the DR3 and DR4 haplotypes) or the presence (in the DR2 haplotype) of Asp57 in the DQ beta-chain. Data on southern European populations challenge this hypothesis because the DR2 haplotype has not been associated negatively with IDDM, as reported in northern European populations. This study on a selected panel of DR2-positive Italian IDDM patients shows that 19 of 21 (90.5%) DR2 haplotypes possess a non-Asp57 DQB allele. Moreover, the same non-Asp57 subtype has a comparatively high frequency (9/28, or 32.1%, DR2 haplotypes) also in the DR2-positive healthy Italian population. The difference between patients and control subjects is significant (P less than 0.0001). This is the largest series of DR2-positive patients analyzed so far. Comparison with cumulated data in various white populations shows a distinct northern European-to-southern European gradient. Toward southern Europe, the relative frequency of the non-Asp57 DR2 subtype increases. Concomitantly, the apparent protective effect of the DR2 haplotype disappears. Therefore, the observed differences in DR2-IDDM association in white populations can be explained adequately by the Asp57 hypothesis, which this study's data strongly support.
Diabetes 1992 Aug
PMID:An explanation for the neutral effect of DR2 on IDDM susceptibility in central Italy. 162 63

MHC associations with IDDM in a Chinese population were studied to investigate genetic susceptibility to the disorder. The frequency of HLA-DR3 was significantly higher in the diabetic patients (19/49 [38.7%] vs. control subjects, 11/105 [10.5%], Pc less than 1.3 x 10(-3), RR = 5.3 [CI 2.3-12.1]), whereas DR4 was not (11/49 [22.4%] vs. 28/105 [26.7%], NS). The frequency of DR3/4 heterozygosity was higher in the diabetic patients (6/49 [12.2%] vs. control subjects, 0/105 [0%], P = 1.7 x 10(-3), RR = 31.5 [CI 3.8-263.6]). The frequency of DR3/9 heterozygosity also was higher in the diabetic patients (6/49 [12.2%] vs. control subjects, 2/105 [1.9%], P = 0.03, RR = 6.2 [CI 3.0-12.7]). No significant associations were noted between DQB1 alleles and IDDM. Among DR4-positive subjects, the frequency of DQB1 allele DQB1*0302 was higher in the diabetic patients (10/11 [90.0%] vs. control subjects, 12/24 [50%], Pc less than 0.05, RR = 7.0 [CI 1.3-38.0]), and the frequency of DQB1*0401 was significantly lower in the diabetic patients (2/11 [18.2%] vs. control subjects, 16/24 [66.7%], Pc = 0.04, RR = 0.1 [CI 0.02-0.46]). No DR4 subtype was associated significantly with IDDM. The frequency of DQA1*0501, a DQA1 allele, was higher in diabetic patients (22/41 [53.7%] vs. control subjects, 20/95 [21.1%], Pc less than 3 x 10(-3), RR = 4.3 [CI 2.0-9.3]). The frequency of DQA1*0301, which has been associated consistently with IDDM in other ethnic groups, was not significantly higher in the diabetic patients in this study (27/41 [65.9%] vs. control subjects, 53/95 [55.8%], NS).(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes 1992 Aug
PMID:Susceptibility to IDDM in a Chinese population. Role of HLA class II alleles. 162 65

The association of certain autoimmune diseases with HLA molecules is being refined through the use of sequence-specific oligonucleotide probes and amino acid sequencing, together with continuing elucidation of the functional features of HLA molecules derived from the milestone description by Bjorkman of the HLA molecular structure. The association of insulin-dependent diabetes mellitus and HLA began with weak associations of Class I antigens (B8 and B15) and progressed to Class II antigens (DR3 and DR4), then to subtypes of DR4 (Dw4, 10, and 14), and now to DQ molecules including the absence of aspartic acid at position 57 of the DQ beta chain and the presence of arginine at position 52 of the DQ alpha chain. In rheumatoid arthritis (RA) the HLA antigen association remains with certain Class II molecules of the DR series (DR4 and DR1) that share amino acid sequences with a restricted number of other DR antigens seen in RA, as well as a segment of the gp 110 protein of the Epstein-Barr virus. Although ankylosing spondylitis has a strong association with the Class I antigen B27, that association is not explained by any of the B27 subtypes defined by monoclonal antibodies, by the eight variable amino acids in B27 subtypes, or by the two unique amino acids on B27. The remarkable antibody cross-reactivity among lymphocytes bearing B27, a synthetic peptide sequence (63-84) of B27, and the 188-193 sequence of K. pneumoniae nitrogenase has provided strong support for molecular mimicry being an important mechanism in the association of HLA molecules with disease.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:HLA molecules in autoimmune diseases. 163 34


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