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)

A series of diabetic patients from 3 centres in South India have been tested for HLA A, HLA B, BF, C2, C4A, C4B and GLO types. For insulin-dependent diabetes mellitus (IDDM) patients there was a significant increase in HLA B8, of BF F and decrease of C4 A6. No significant variation in HLA, BF, C2 or GLO frequencies was found in non-insulin-dependent diabetes mellitus (NIDDM) patients, but there was a significant decrease in C4B 1 and an increase in C4B 2. The HLA and BF association in South Indian IDDM patients is very different from that reported previously in North India.
Diabetes Res Clin Pract 1985 Mar
PMID:HLA, complement C2, C4, properdin factor B and glyoxalase types in South Indian diabetics. 387 24

The families of 41 probands with type I (insulin-dependent) diabetes mellitus (IDDM) were typed for HLA-A, HLA-B, and HLA-DR antigens in addition to the complement polymorphisms C2, C4A, C4B, and Bf. All of these loci are encoded on the short arm of human chromosome 6 in a narrow region. Alleles at HLA-B (8, 15, 18, and 40), HLA-DR (3 and 4), and Bf (F1) have been associated with increased relative risk (RR) for IDDM, while HLA-B7 and HLA-DR2 have been associated with decreased RR for IDDM. This study confirms those significant risks in addition to confirming increased risk for the null (silent) allele for C4A (C4AQ0) and a rare C4B variant (C4B2.9). The significantly associated antigens (alleles) and risks were: HLA-B8 (RR = 3.1), HLA-DR3 (RR = 5.2), HLA-DR4 (RR = 4.3), and BfF1 (RR = 7.1), in addition to C4AQ0 (RR = 2.8) and C4B2.9 (RR = 12.6). Significantly low risk was associated only with HLA-DR2 (RR = 0.1). In a recent study, we defined five high-risk haplotypes that were determined solely by HLA-B, Bf, and HLA-DR (B8-BfS-DR3, B8-BfS-DR4, B15-BfS-DR4, B18-BfF1-DR3, and B40-BfS-DR4). By inclusion of information from the complement polymorphism, we have defined in greater detail three of these five high-risk haplotypes. One previously identified haplotype (B40-BfS-DR4) showed no complement clustering, while the rare high-risk haplotype (B8-BfS-DR4) was seen only once in this smaller sample.(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes 1985 May
PMID:Complement and HLA. Further definition of high-risk haplotypes in insulin-dependent diabetes. 398 76

The demonstration of immune response genes in man has been difficult, although there is evidence for genes linked to the MHC in mouse and guinea pig that control both the specificity and magnitude of immune responses. A number of features of the antibody response to the Rh D antigen, such as the failure of some individuals at risk to respond, the restricted immunoglobulin class, subclass, and light chain type of the antibody produced, and the presumed minor structural difference between Rh D antigen and its allelic product, all suggest that one or at most a few immune response genes are involved. Typing for the four MHC-linked complement genes BF, C2, C4A, and C4B was carried out in 52 independently ascertained Caucasian individuals with significant anti-D titers. A control population of 623 normal Caucasian chromosomes was also studied. In patients with anti-D antibodies, the frequency of BF F1 (0.04 vs 0.0064 for 623 chromosomes, p less than 0.003); of C4A 3 (0.769 vs 0.631, p less than 0.006); and of C4B Q0 (0.25 vs 0.104, p less than 0.00004) were all increased. These three alleles are found in the common complotype BF 8F1,C2 C,C2A 3, C4B Q0, and presumably represent a single extended haplotype of 6p associated with (and presumably containing a gene for) the immune response to RhD. This complotype has a 0.6% frequency in 623 normal control chromosomes, but is also increased in patients with insulin-dependent diabetes mellitus and with membranous glomerulonephritis.
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PMID:MHC determinants of response to Rh immunization. 619 42

Homozygous typing cells from 13 normal HLA-A1, B8, Dw3, DR3 and five normal HLA-A26, Bw38, Dw10, DR4 individuals were typed for the following markers: HLA-SB, MB, MT; complement proteins BF, C2, C4A, C4B; and GLO. Ninety-one percent of A1, B8, Dw3, DR3 homozygous individuals (HI) tested were homozygous for BF*S, C2*C, C4A*QO, and C4B*1 (SCO1 complotype), which indicates that the SCO1 complotype is in linkage disequilibrium with the A1, B8, DR3 haplotype in randomly selected normal populations. Sixty-seven percent of HLA-A1, B8, Dw3, DR3, SCO1 positive HI also expressed SB1; since the frequency of SB1 in random Caucasian populations is 11.2%, this finding indicates that SB1 is in linkage disequilibrium with the A1, B8, DR3, SCO1 extended haplotype. All HI with the A26, Bw38, Dw10, DR4 haplotype were homozygous for both SC21 and SB4, suggesting that SC21 and SB4 should be included in the A26, Bw38, Dw10, DR4 extended haplotype. On the other hand, neither of the GLO markers were found in association with either haplotype. The results of this study indicate that HLA-SB is included in some extended haplotypes and may be important in these markers for diseases such as insulin-dependent diabetes mellitus. This study also demonstrated an apparent influence of HLA-SB on primary mixed lymphocyte culture (MLC) responses. The mean relative response of primary MLCs between individuals matched for HLA-A, B, D, DR, MB and MT but not SB was 40% of that for the MLCs with mismatched HLA-D, significantly higher than the MLCs matched for all HLA and complotypes.
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PMID:Linkage disequilibrium of HLA-SB1 with the HLA-A1, B8, DR3, SCO1 and of HLA-SB4 with the HLA-A26, Bw38, Dw10, DR4, SC21 extended haplotypes. 623 24

The fourth component of complement (C4) in man, is coded for by two separate but closely linked loci (C4A and C4B) within the major histocompatibility region (MHC), on the short arm of chromosome 6. Like class I and II loci of this region, the C4 genes are highly polymorphic with more than 30 alleles, including null alleles, assigned to the two loci. This extensive polymorphism, based mainly on electrophoretic mobility, provides a useful marker for studies of disease susceptibility. Several disorders, including systemic lupus erythematosus and type I diabetes, show associations with C4 phenotypes. We have used the technique of Southern with a C4 specific probe to examine the genomic DNA of individuals typed for C4 by protein electrophoresis. We have identified 10.7 and 3.8 kilobase (kb) BglII restriction fragments in each of 9 unrelated individuals with a C4A6 allele, and in none of 22 unrelated individuals in whom this allele was not expressed. This clear correlation of restriction fragment length polymorphism with C4 phenotype provides a precise basis for analysis of C4 polymorphism. It is likely to be of value in clinical investigations of autoimmune disease.
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PMID:Correlation between a DNA restriction fragment length polymorphism and C4A6 protein. 631 64

HLA antigens, complement allotypes, insulin antibodies and thyrogastric autoantibodies were determined in 69 patients with Type 1 (insulin-dependent) diabetes defined by a tendency to ketosis, non-obesity and insulin requirement within 2 years of diagnosis. Analysis of HLA and C4 allotypes suggested that Type 1 diabetes was associated with only certain DR3- and DR4-containing supratypes. Low antibody response to insulin was associated with all HLA-DR3, being present in 89% of those with DR3 compared with 48% of those without. Thyrogastric autoantibodies were associated with a null allele at the C4A locus, usually with HLA-B8-C4AQO-C4B1-BfS-DR3. These results indicate that, unlike Type 1 diabetes, low insulin antibody response was associated with all HLA-DR3. Thyrogastric autoantibodies, on the other hand, were associated with a null allele at the C4A locus. It is probable that while interaction between certain HLA-DR3 and DR4-containing supratypes is important in conferring susceptibility to Type 1 diabetes, other manifestations of autoimmunity are associated with supratypes containing C4AQ0, and in particular the diabetogenic supratype HLA-B8-C4AQ0-C4B1-BfS-DR3.
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PMID:Thyrogastric autoimmunity and MHC associated alleles at the C4 locus in patients with type 1 (insulin-dependent) diabetes. 633 53

C4 gene and haplotype frequencies were calculated from phenotype data of 380 unrelated Caucasian patients with insulin dependent (type 1) diabetes mellitus and were compared with analogous frequencies of 382 unrelated healthy Caucasian individuals. In diabetics, a significantly increased frequency of the rare allele C4B 3 (p less than 10(-7] and of the silent alleles C4A Q0 (p less than 10(-7] and B Q0 (p less than 0.002) was observed. Accordingly, insulin dependent diabetes is associated with partial C4 deficiency, which may contribute to the pathogenesis of the disease.
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PMID:Gene and haplotype frequencies of the fourth component of complement (C4) in type 1 diabetics and normal controls. 648 29

The complement component C4 variants C4A 4, C4B 4 and C4B Q0 were found to be significantly increased in 64 black patients with Type 1 (insulin-dependent) diabetes compared with 169 black control subjects, yielding relative risks of 3.3, 2.9 and 3.4, respectively. The increased frequencies of C4B 4 and C4B Q0 in black Type 1 diabetic patients are similar to those found in Caucasoid Type 1 diabetic patients. The data suggest that Type 1 diabetes in black Americans may be partially due to admixture of genes from whites.
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PMID:The complement component C4 in black Americans with type 1 (insulin-dependent) diabetes mellitus. 671 36

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

Inclusion body myositis (IBM) is defined clinically by a characteristic pattern of progressive proximal and distal limb muscle weakness and resistance to steroid therapy, and histologically by the presence of distinctive rimmed vacuoles and filamentous inclusions as well as a mononuclear infiltrate in which CD8+ T cells are predominant. Muscle damage is believed to be mediated by autoimmune mechanisms, but very little information is available on the immunogenic features of IBM. MHC class I and DR antigens were typed on 13 caucasoid patients with IBM using standard serological techniques or by allele-specific oligonucleotide typing. Complement components C4 and properdin factor B (Bf) were typed by immunofixation after electrophoresis. Restriction fragment length polymorphisms (RFLP) in the class III region were analysed using cDNA probes for C4 and 21-hydroxylase (CYP21) after Taq 1 digestion. IBM was associated with DR3 (92%), DR52 (100%) and HLA B8 (75%). The phenotype data were examined for likely haplotypes by considering together the alleles at the class I, DR and complement loci along with the C4 and CYP21 RFLP. Ten of the DR3+ subjects had a 6.4-kb C4-hybridizing fragment characteristic of a deletion of C4A and CYP21-A. These patients probably carried all, or at least the class II and III regions, of the extended haplotype marked by B8/C4A*Q0/C4B1/BfS/DR3/DR52, which has been associated with several autoimmune diseases and is present in 11% of the healthy caucasoid population. Of the remaining subjects, two had evidence of the extended haplotype marked by B18/C4A3/C4BW*0/BfF1/DR3, which is present in less than 5% of the healthy population and has been associated with insulin-dependent diabetes mellitus. These data provide support for an autoimmune etiology for, and genetic predisposition to, IBM.
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PMID:HLA associations with inclusion body myositis. 792 82


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