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)

48 Tunisian people suffering from the IDDM auto-immune disease were compared to 35 control healthy persons for the polymorphisms of the complement BF, C2 and C4 proteins and genes, of the IgG (Gm allotypes) as well as of the TNF alpha and TCR C beta genes. Our study shows that the BFF1-C4A3-C4BQO and BFS-C4AQ0-C4B1 complotypes are associated to IDDM (RR of 2.97 and 3.07 respectively), as previously reported for other circummediterranean populations. The frequency of the Gm 21.28; 1.17; .. haplotype is increased, but not significantly, among the patients. The RFLP analysis reveals that the 2.65 kb SacI allelic restriction fragment of the C2 gene may be considered as a genetic marker of susceptibility to IDDM because its frequency raises to 0.206 among the patients vs 0.021 in the healthy individuals (p less than 0.001). The frequencies of the C4AQ0 and C4BQ0 alleles are more important among the IDDM patients than within the control sample, but the only C4BQ0 allele frequency is significantly increased. Both C4AQ0 and C4BQO result mainly from deletions. The frequencies of the allelic restriction fragments of the TNF alpha and TCRC beta genes are not significantly different among the patients and the controls. But the small sample size don't allow us to conclude definitively. It would be very interesting to extend the RFLP analysis to the TCR V beta and V alpha gene regions on more numerous samples.
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PMID:[Immunogenetic markers (BF, C2, C4, 21-OH, TNF alpha, TCR beta, Ig) and insulin-dependent diabetes in the Tunisian population: serological and molecular study]. 168 90

Human cDNA probes for 21-hydroxylase (21-OH) and for complement component C4 are used on restriction digests of the members of several families with interesting supratypes. The presence of two Taq I fragments of 3.7 kb and 3.2 kb in size with a 21-OH probe is confirmed in most individuals who show no evidence of C4 deletions or 21-OH deficiency. Most individuals also show a doublet of weakly hybridizing bands at approximately 2.5 kb, the smaller of which is part of the 21 A gene. The arrangement of the 21-OH genes on disease-associated supratypes was examined, and it is shown that copies of the same supratype from unrelated individuals are usually identical. Evidence is provided for deletions of 21A on the B8, C4AQ0, C4B1, BfS, DR3 and B18, C4A3, C4BQ0, BfF1, DR3 supratypes and a duplication of 21A on the B14, C4A2, C4B1/B2, BfS supratype. Gene rearrangements may be relevant to diseases such as juvenile onset diabetes mellitus.
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PMID:Rearrangement of 21-hydroxylase genes in disease-associated MHC supratypes. 300 40

From the study of HLA, A, B, C, DR, Bf and C4A, C4B alleles in 287 insulin-dependent diabetes mellitus patients and 108 controls, comparisons were made between 424 diabetic and 216 normal extended haplotypes. In the "cis" situation (haplotype), the highest relative risks (RR) for IDDM were borne by multiloci allelic associations, mainly DR/complement alleles, rather than by DR3 or DR4 considered alone. Susceptibility was strongly associated with two extended haplotypes (Aw30, Cw5, B18, C4BQ0, C4A3, BfF1, DR3 and A2, Cw3, B15, C4Bx, C4A3, BfS, DR4) or their smaller segments. Two haplotypes, S31 associated with DR2 or DR5 and F31 associated with DRw6 or DR7 had a protective effect. In the "trans" situation (opposite haplotype) the large excess of DR3/DR4 heterozygotes was not the only distortion observed. An excess of DR1 (57%) and of C4BQ0 (40%) was noted among non DR3, non DR4 haplotypes in diabetics compared to normal individuals (26% and 23%, respectively, P less than 0.01, 0.05). Homozygotes for DR3 or DR4 were not increased, and other homozygotes were decreased compared to controls. The protective antigens HLA DR2, DR5 and DR7 seemed not to be distributed randomly: their putative protective effect was not observed in the case of combination with DR1 or a B18, DR3 haplotype. DR2 was never found homozygous or combined with DR5. These results suggest that susceptibility to IDDM is generated by both cis and trans interactions between genes or gene products of the HLA region.
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PMID:Study of cis and trans interactions between extended HLA-haplotypes in insulin-dependent diabetes. 340 91