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)

Present knowledge regarding the HLA system and the association between HLA antigens and insulin-dependent type 1 diabetes mellitus (IDDM) is reviewed. The heterogeneity of diabetes, immunogenetically speaking, is emphasized. Results are reported for HLA typing in 18 cases of known IDDM recently diagnosed and observed at the Karen Bruni Diabetes Center in approximately one year (1981-82). The frequency of HLA antigens B7, B8 (in linkage disequilibrium with DR3), B15 (in linkage disequilibrium with DR4) and B18 was examined in comparison with a Piemontese control group. The X2 method was used for calculating the relative risk and statistic importance of the intensity of association. IDDM susceptibility in association with HLA-B18 was confirmed and resulted significantly higher in our cases in respect to controls. Correlations without, however, reliable importance, have also been found between HLA-B8 and B15. IDDM protection by HLA-B7 was not confirmed. Diabetes began during the winter, from October to February, in 10 out of 18 cases, and some were positively related to a previous respiratory viral infection. Previous virus infection was found in three B7-positive cases. The more frequent arousal of diabetic symptoms during the winter in subjects positive for HLA-B8 and B18 was confirmed in 7 out of 8 cases. This work demonstrates the current practicability of HLA typing of recently diagnosed insulin-dependent diabetic in a Diabetes Center. This element helps to a more correct classification--on a subclinical basis--of initial cases of type 1 and 2 diabetes and can be used for possible problems during the course of insulin therapy.
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PMID:[The HLA system and insulin-dependent diabetes mellitus. A review and personal studies]. 638 59

We have studied major histocompatibility complex markers in Caucasian patients with type I diabetes mellitus and their families. The frequencies of extended haplotypes that were composed of specific HLA-B, HLA-DR, BF, C2, C4A, and C4B allelic combinations, which occurred more commonly than expected, were compared on random diabetic and normal chromosomes in the study families. We demonstrated that all of the previously recognized increases in HLA-B8, B18, B15, DR3, and perhaps DR4 could be ascribed to the increase among diabetic haplotypes of a few extended haplotypes: [HLA B8, DR3, SC01, GLO2]; [HLA-B18, DR3, F1C30]; [HLA-B15, DR4, SC33]; and [HLA-BW38, DR4, SC21]. In fact, HLA-DR3 on nonextended haplotypes was "protective", with a relative risk considerably less than 1.0. There was a paucity or absence among diabetic patients of several extended haplotypes of normal chromosomes, notably [HLA-B7, DR2, SC31] and [HLA-BW44, DR4, SC30]. The extended haplotype [HLA-BW38, DR4, SC21] is found only in Ashkenazi Jewish patients, which suggests that extended haplotypes mark specific mutations that arise in defined ethnic groups. The data show that no known MHC allele, including HLA-DR3 and possibly HLA-DR4, is per se a marker for or itself a susceptibility gene for type I diabetes. Rather, extended haplotypes, with relatively fixed alleles, are either carriers or noncarriers of susceptibility genes for this disease. Thus, the increased frequency (association) or the decreased frequency (protection) of individual MHC alleles is largely explainable by these extended haplotypes.
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PMID:Extended major histocompatibility complex haplotypes in type I diabetes mellitus. 674 3

We found the rare properdin factor B(Bf) variant F1 to be present in 11% of 72 patients suffering from insulin-dependent diabetes (IDDM) compared with 2% among 150 normal controls. BfF1 thus confers a relative risk for IDDM of 5.55. All eight patients and three controls who were BfF1 positive were also HLA-B18 positive, reflecting the strong linkage disequilibrium between these two factors. We suggest that BfF1 marks a 'diabetogenic' B18-bearing HLA haplotype. Studies of unselected families with one or more affected members suggest that the B18, BfF1 does not necessarily segregate with IDDM phenotype. This study provides further evidence for the genetic heterogeneity of IDDM.
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PMID:Properdin factor B(Bf) allele BfF1 specifies an HLA-B18 diabetogenic haplotype. 692 67

The Basques were previously shown to present a high frequency of HLA-B18 and BfF1, which are known to be associated with insulin dependent diabetes mellitus (IDDM). During the VIII International Histocompatibility Workshop, we studied HLA-A, B, C, DR; Bf, C4 and GLO.I polymorphisms in 51 unrelated French Basque IDDM patients and in 50 controls. Haplotypes were established by family studies in all controls and some patients. Two haplotypes were frequently found in the controls: HLA-A1, Bw57, BfS, C4 F1S, DR7 and HLA-Aw30, Cw5, B18, Bf F1, C4Fs degree, DR3. The first one was not found in the patients. All the components of the second haplotype had increased frequencies possibly as a consequence of linkage disequilibrium with HLA-DR3: a highly significant association between IDDM and HLA-DR3 was observed (90.2% vs 24.0%, relative risk (RR) = 29.1, P less than 10(-11)). The HLA-DR4 frequency was slightly increased (37.3% vs 16.0%), and HLA-DR2 was not found. The silent allele C4s degree was particularly associated with early diagnosed IDDM (86.7% in patients with age at onset under 20 years vs 57.1% in other patients, P less than 0.02). The high relative risk for HLA-DR3/DR4 heterozygous vs that of individuals, possibly HLA-DR3 homozygous, supported the hypothesis that two HLA-DR linked genetic factors could be involved in the inheritance of IDDM susceptibility.
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PMID:HLA-A, B, C, DR antigens, Bf, C4 and glyoxalase I (GLO) polymorphisms in French Basques with insulin-dependent diabetes mellitus (IDDM). 695 94

Seventy-four North American Caucasian insulin dependent diabetics are presented and compared to 100 healthy controls relative to HLA-A and B locus antigens. A highly significant increase in the frequency of HLA-B8 was found (p < 0.01, relative risk 3.67). The presence of HLA-A11 conferred statistically significant protection against disease development in these patients (p < 0.01, relative risk 0.19). There was no significant difference in the frequency of HLA-B7, B8, or B15 between the study and control groups. The patient group does show a significant increase in heterozygosity for HLA-B8 and HLA-B15 when compared to healthy controls (p < 0.05, relative risk 7.17). Increased incidence of HLA-B18 has previously been noted in French and English populations only. Since most of our HLA-B18 patients are of English extraction, it is concluded tht the altered incidence of the HLA-B18 allele in insulin dependent diabetes does persist in this migratory European population.
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PMID:Decreased incidence of HLA-A11 and increased incidence of HLA-B8 in a North American population of insulin dependent diabetics. 700 49

Although multiple sclerosis (MS) usually appears isolated from other autoimmune disorders, an overlap with type 1 diabetes mellitus (T1DM) has been described in Sardinia, where T1DM-associated haplotype HLA-B18-DR3-DQ2 contributes to MS risk. To determine whether in our population MS patients show signs of pancreatic autoimmunity and share this haplotype, sera from 49 MS patients were tested for GAD, IA2, and CPH autoantibodies, and MICA exon 5 polymorphism was genotyped in 30 patients. Pancreatic autoimmune markers were not present among MS patients, nor was any MICA allele associated with MS. Overall, there is no evidence supporting a T1DM/MS overlap in our population.
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PMID:No evidence of pancreatic autoimmunity among patients with multiple sclerosis. 1569 7

Tumor necrosis factor (TNF) and lymphotoxin alpha (LT-alpha) are immunomodulators that have been hypothesized to contribute to susceptibility to type 1 diabetes (T1D). Several polymorphisms in the TNF and LT-alpha loci have been extensively studied for T1D association, with conflicting reports. In this study, we examined two TNF variants and one LT-alpha variant for T1D association in 283 Caucasian, multiplex T1D families for which complete human leukocyte antigen (HLA) genotyping data are available. Initially, association with T1D was seen for LT-alpha A1069G (intron A, p=0.011, rs909253) and TNF G(-308)A (p<1x10(-5), rs1800629), but no association was observed for TNF G(-238)A (rs361525). After adjusting the data for linkage disequilibrium (LD) with DRB1-DQB1 haplotypes, however, only one polymorphism, TNF G(-238)A showed significant association with T1D (p<0.006). When HLA-DR3 haplotypes were examined, the A allele of TNF G(-238)A was significantly overtransmitted to affected offspring (p<0.009). Including HLA-B data in the analysis revealed that TNF (-238)A is present exclusively on DR3 haplotypes that also carry HLA-B18. Transmission proportion of B18-DR3 haplotypes did not differ between those with TNF (-238)A and those with TNF (-238)G. Thus, variation at TNF does not affect the T1D risk for B18-DR3 haplotypes, and the apparent association of TNF(-238)A with T1D may simply reflect its presence on a high-risk haplotype.
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PMID:Linkage disequilibrium with predisposing DR3 haplotypes accounts for apparent effects of tumor necrosis factor and lymphotoxin-alpha polymorphisms on type 1 diabetes susceptibility. 1717 49