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)

HLA Class II polymorphisms were analysed in 27 families with at least one Type I diabetic proband using Southern blotting technique according to 10th Histocompatibility Workshop Standards. The probes used were DRB, DQA1, DQB1 and DOB. We have studied 108 haplotypes and performed segregation analysis with HLA serology and restriction fragment length polymorphism (RFLP) data and compared "affected" with "non-affected" haplotypes (not inherited by IDDM patients). RFLPs correlated well with DR and DQ serology and detected additional polymorphisms. In particular, DQB polymorphism analysis showed segregation of the DQw3 splits with 88.5% of the DR4 affected haplotypes bearing the DQw3.2 split (now DQw8) and 11.5% the DQw3.1 split (now DQw7) while in the non-affected DR4 haplotypes 33.3% were DQw3.2 and 66.6% were DQw3.1. Haplotype analysis showed that DR4-DQw3.2 was in strong linkage with the U fragment (2.1 kb Taq I) of DQA2 (DX alpha) and with the L fragment (5.4 kb BamH I) of DOB. This study confirms previous observations of DQB polymorphisms in heterozygous IDDM patients, supports the protective effect of DQw3.1 (DQw7) against the development of the disease and demonstrates the importance of DQw3.2 (DQw8) for susceptibility to Type I diabetes.
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PMID:Restriction fragment length polymorphism analysis of HLA haplotypes in families with type I diabetes mellitus. 196 92

We have investigated restriction fragment length polymorphism (RFLP) of HLA and non-HLA regions of the genome in the homogeneous Danish population. Insulin-dependent diabetes mellitus (IDDM) patients and healthy individuals were selected for being HLA-DR 3/4 heterozygous to evaluate the influence of genes other than DR on disease susceptibility. Five different probes were used: HLA alpha and beta DQ (chromosome 6), the Ins 310 genomic fragment which detects a polymorphic region 5' to the insulin gene (chromosome 11), and cDNA for the constant regions of the T cell receptor alpha and beta genes (chromosomes 14 and 7). Fifteen cells homozygous for the HLA-D region were used to obtain reference DNA patterns. This allowed us to describe four splits among the HLA-DQw3 haplotypes (DQw3.1 to DQw3.4). The two new haplotypes DQw3.3 and DQw3.4 do not code for the TA10 serological marker which is found on DQw3.1 positive cells. One-hundred per cent of IDDM patients were typed as DQw3.2 versus 68 per cent for controls (p = 0.003). However, our results do not indicate a role for the Ins 310 or for the alpha DX locus region in IDDM susceptibility, in contrast to previous reports by others. The restriction enzymes that we have used did not reveal significant differences between DNA patterns of patients and controls with probes for the constant region of the T cell receptor genes.
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PMID:Restriction fragment length polymorphism of HLA and non-HLA genes in DR3/4 heterozygous Danish insulin-dependent diabetic patients and healthy individuals: reassessment of the influence of alpha DX and insulin-linked polymorphic loci, and new splits of DQw3 haplotypes. 256 78

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