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Sökning: WFRF:(Hagopian William)

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  • Graham, J, et al. (författare)
  • Genetic effects on age-dependent onset and islet cell autoantibody markers in type 1 diabetes.
  • 2002
  • Ingår i: Diabetes. - : American Diabetes Association Inc.. - 1939-327X .- 0012-1797. ; 51:5, s. 1346-1355
  • Tidskriftsartikel (refereegranskat)abstract
    • Age-dependent associations between type 1 diabetes risk genes HLA, INS VNTR, and CTLA-4 and autoantibodies to GAD65 (GADAs), ICA512/IA-2, insulin, and islet cells were determined by logistic regression analysis in 971 incident patients with type 1 diabetes and 702 control subjects aged 0-34 years. GADAs were associated with HLA-DQ2 in young but not in older patients (P = 0.009). Autoantibodies to insulin were negatively associated with age (P < 0.0001) but positively associated with DQ8 (P = 0.03) and with INS VNTR (P = 0.04), supporting possible immune tolerance induction. ICA512/IA-2 were negatively associated with age (P < 0.0001) and with DQ2 (P < 0.0001) but positively associated with DQ8 (P = 0.04). Males were more likely than females to be negative for GADA (P < 0.0001), autoantibodies to islet cells (P = 0.04), and all four autoantibody markers (P = 0.004). The CTLA-4 3' end microsatellite marker was not associated with any of the autoantibodies. We conclude that age and genetic factors such as HLA-DQ and INS VNTR need to be combined with islet autoantibody markers when evaluating the risk for type 1 diabetes development.
  • Gupta, Manu, et al. (författare)
  • MHC class I chain-related gene-A is associated with IA2 and IAA but not GAD in Swedish type 1 diabetes mellitus
  • 2006
  • Ingår i: Annals of the New York Academy of Sciences. - : Wiley-Blackwell. - 0077-8923. ; 1079, s. 229-239
  • Tidskriftsartikel (refereegranskat)abstract
    • In type I diabetes mellitus (T1DM), the frequency of antibodies against insulin (IAA), glutamic acid decarboxylase-65 (GAD65), ICA512/IA2 (IA2), and islet cell antigens (ICA) vary with human leukocyte antigen (HLA) composition of the patient. IAA, IA2 autoantibodies, and ICA are increased in DQ8 positives; GAD65 antibodies are increased in DQ2 positives. MHC class I chain-related gene-A (MICA) is another genetic marker that has been proposed to be associated with T1DM. In this article, we looked at microsatellite polymorphism of MICA and its association with autoantibodies (IAA, IA2, and GAD65) in Swedish T1DM patients and if the association explains its importance in early events in autoimmune response. We studied 635 T1DM patients between 0-35 years. Frequency of MICA5/5 was positively associated with the formation of IAA and IA2 antibodies considered individually or in combination (odds ratio 10111, 95% Cl, Pc: [IAA+ versus IAA-] : 4.94, 2.09-11.62, < 0.0005; [IA2+ versus IA2-] : 2.65,1.52-4.59,0.0015; [IAA and/or IA2+ versus rest]: 9.83, 2.37-40.78, < 0.0015; [IAA and IA2+ versus rest]: 3.51, 2.01-6.15, < 0.0015). Also, -5.115.1 was increased in IAA+ patients compared to IAA- patients (2.82, 1.64-4.83, < 0.0005). All patients positive for -5/5 developed at least one of the three antibodies. Frequency of MICA5.1 was decreased in IAA+ (0.54, 0.36-0.81, 0.017), in IA2A+ (0.63, 0.45-0.88, 0.04), in IAA and/or IA2A+ (0.52, 0.33-0.84, 0.044), and in IAA and IA2A+ (0.55, 0.39-0.78, 0.0055) patients when compared with patients negative for corresponding antibodies. Frequency of MICA9, 5/5.1, and 5.1/9 was decreased in IAA+ compared to IAA- patients (0.51, 0.32-0.79,0.021; 0.22, 0.11-0.44, < 0.005; and 0.39, 0.22-0.69, 0.026, respectively). Frequency of MICA9 and -5.1/9 was also decreased in IAA and/or IA2 antibody-positive patients while MICA5/5.1 decreased in patients positive for IAA and IA2 antibody both together. IAA and IA2 antibodies are believed to appear early during the autoimmune reaction against beta cells. Thus, according to our data, MICA-5/5 and -5.1/5.1 is associated with early autoimmunity in T1DM patients. Our study suggests that MICA gene polymorphism is associated with autoantibody formation and that the polymorphism especially MICA5/5 and -5.1/5.1 are important in early events of autoimmune reaction.
  • Hagopian, William A., et al. (författare)
  • Glutamate decarboxylase-, insulin-, and islet cell-antibodies and HLA typing to detect diabetes in a general population-based study of Swedish children
  • 1995
  • Ingår i: Journal of Clinical Investigation. - : Am Soc Clin Investig. - 0021-9738. ; 95:4, s. 1505-1511
  • Tidskriftsartikel (refereegranskat)abstract
    • Most autoimmune diabetes occurs in those without a diabetic relative, but few cases are identifiable prospectively. To model general population prediction, 491 consecutive newly diabetic children from all of Sweden were tested for autoantibodies to glutamate decarboxylase (GAD65ab), insulin (IAA), and islet cells (ICA), and for HLA-DQ genotypes by PCR; 415 matched control children were tested in parallel. GAD65ab sensitivity/specificity was 70/96%, versus 84/96% for ICA, 56/97% for IAA, 93/93% (any positive), 39/99.7% (all positive), and 41/99.7% (GAD65ab plus IAA). The latter's 25% predictive value was not improved by requiring concomitant high-risk HLA genotypes. GAD65ab were associated with DQA1*0501/B1*0201 (DQ2; P = 0.007) but not DQA1*0301/B1*0302 (DQ8), and IAA with DQA1*0301/B1*0302 (DQ8; P = 0.03) but not DQA1*0501/B1*0201 (DQ2). GAD65ab were more prevalent in females than males (79 vs. 63%; P < 0.0001) but did not vary with onset age nor season. Combining the three antibody assays yielded sufficient sensitivity for screening. GADab were relatively sensitive/specific for diabetes, but even with HLA marker combinations yielded predictive values insufficient for early immunointervention in the low-prevalence general population.
  • Lindblad-Toh, Kerstin, et al. (författare)
  • Genome sequence, comparative analysis and haplotype structure of the domestic dog.
  • 2005
  • Ingår i: Nature. - 1476-4687. ; 438:7069, s. 803-19
  • Tidskriftsartikel (refereegranskat)abstract
    • Here we report a high-quality draft genome sequence of the domestic dog (Canis familiaris), together with a dense map of single nucleotide polymorphisms (SNPs) across breeds. The dog is of particular interest because it provides important evolutionary information and because existing breeds show great phenotypic diversity for morphological, physiological and behavioural traits. We use sequence comparison with the primate and rodent lineages to shed light on the structure and evolution of genomes and genes. Notably, the majority of the most highly conserved non-coding sequences in mammalian genomes are clustered near a small subset of genes with important roles in development. Analysis of SNPs reveals long-range haplotypes across the entire dog genome, and defines the nature of genetic diversity within and across breeds. The current SNP map now makes it possible for genome-wide association studies to identify genes responsible for diseases and traits, with important consequences for human and companion animal health.
  • Littorin, Bengt, et al. (författare)
  • Islet cell and glutamic acid decarboxylase antibodies present at diagnosis of diabetes predict the need for insulin treatment : A cohort study in young adults whose disease was initially labeled as type 2 or unclassifiable diabetes
  • 1999
  • Ingår i: Diabetes Care. - : American Diabetes Association. - 0149-5992 .- 1935-5548. ; 22:3, s. 409-412
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVE - To clarify the predictive value of islet cell antibody (ICA) and GAD65 antibody (GADA) present at diagnosis with respect to the need for insulin treatment 6 years after diagnosis in young adults initially considered to have type 2 or unclassifiable diabetes. RESEARCH DESIGN AND METHODS - The patient material was representative of the entire Swedish population, consisting of patients who were 15-34 years old at diagnosis of diabetes in 1987-1988 but were not considered to have type 1 diabetes at onset. At follow-up, 6 years after the diagnosis, it was noted whether the patient was treated with insulin. The presence of ICA was determined by an immunofluorescence assay, and GADAs were measured by a radioligand assay. RESULTS - Six years after diagnosis, 70 of 97 patients were treated with insulin, and 27 of 97 patients were treated with oral drugs or diet alone. At diagnosis, ICAs and GADAs were present in 41 (59%) of 70 patients and 41 (60%) of 68 patients, respectively, of those now treated with insulin, compared with only 1 (4%) of 26 patients and 2 (7%) of 27 patients who were still not treated with insulin. For either ICA or GADA, the corresponding frequencies were 50 (74%) of 68 for patients who were later treated with insulin and 3 (12%) of 26 for those who were still not treated with insulin, respectively The sensitivity for later insulin treatment was highest (74%) for the presence of ICA or GADA, and the specificity was highest (100%) for ICA and GADA. The positive predictive value was 100% for the combination of ICA and GADA, 98% for ICA alone, and ~95% for GADA alone. CONCLUSIONS - Determination of the presence of ICA and GADA at diagnosis of diabetes improves the classification of diabetes and predicts the future need of insulin in young adults.
  • Andrén Aronsson, Carin, et al. (författare)
  • Association of gluten intake during the first 5 years of life with incidence of celiac disease autoimmunity and celiac disease among children at increased risk
  • 2019
  • Ingår i: JAMA - Journal of the American Medical Association. - : American Medical Association. - 0098-7484. ; 322:6, s. 514-523
  • Tidskriftsartikel (refereegranskat)abstract
    • Importance: High gluten intake during childhood may confer risk of celiac disease. Objectives: To investigate if the amount of gluten intake is associated with celiac disease autoimmunity and celiac disease in genetically at-risk children. Design, Setting, and Participants: The participants in The Environmental Determinants of Diabetes in the Young (TEDDY), a prospective observational birth cohort study designed to identify environmental triggers of type 1 diabetes and celiac disease, were followed up at 6 clinical centers in Finland, Germany, Sweden, and the United States. Between 2004 and 2010, 8676 newborns carrying HLA antigen genotypes associated with type 1 diabetes and celiac disease were enrolled. Screening for celiac disease with tissue transglutaminase autoantibodies was performed annually in 6757 children from the age of 2 years. Data on gluten intake were available in 6605 children (98%) by September 30, 2017. Exposures: Gluten intake was estimated from 3-day food records collected at ages 6, 9, and 12 months and biannually thereafter until the age of 5 years. Main Outcomes and Measures: The primary outcome was celiac disease autoimmunity, defined as positive tissue transglutaminase autoantibodies found in 2 consecutive serum samples. The secondary outcome was celiac disease confirmed by intestinal biopsy or persistently high tissue transglutaminase autoantibody levels. Results: Of the 6605 children (49% females; median follow-up: 9.0 years [interquartile range, 8.0-10.0 years]), 1216 (18%) developed celiac disease autoimmunity and 447 (7%) developed celiac disease. The incidence for both outcomes peaked at the age of 2 to 3 years. Daily gluten intake was associated with higher risk of celiac disease autoimmunity for every 1-g/d increase in gluten consumption (hazard ratio [HR], 1.30 [95% CI, 1.22-1.38]; absolute risk by the age of 3 years if the reference amount of gluten was consumed, 28.1%; absolute risk if gluten intake was 1-g/d higher than the reference amount, 34.2%; absolute risk difference, 6.1% [95% CI, 4.5%-7.7%]). Daily gluten intake was associated with higher risk of celiac disease for every 1-g/d increase in gluten consumption (HR, 1.50 [95% CI, 1.35-1.66]; absolute risk by age of 3 years if the reference amount of gluten was consumed, 20.7%; absolute risk if gluten intake was 1-g/d higher than the reference amount, 27.9%; absolute risk difference, 7.2% [95% CI, 6.1%-8.3%]). Conclusions and Relevance: Higher gluten intake during the first 5 years of life was associated with increased risk of celiac disease autoimmunity and celiac disease among genetically predisposed children.
  • Beyerlein, Andreas, et al. (författare)
  • Progression from islet autoimmunity to clinical type 1 diabetes is influenced by genetic factors : Results from the prospective TEDDY study
  • 2019
  • Ingår i: Journal of Medical Genetics. - : BMJ Publishing Group. - 0022-2593. ; 56:9, s. 602-605
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Progression time from islet autoimmunity to clinical type 1 diabetes is highly variable and the extent that genetic factors contribute is unknown. Methods: In 341 islet autoantibody-positive children with the human leucocyte antigen (HLA) DR3/DR4-DQ8 or the HLA DR4-DQ8/DR4-DQ8 genotype from the prospective TEDDY (The Environmental Determinants of Diabetes in the Young) study, we investigated whether a genetic risk score that had previously been shown to predict islet autoimmunity is also associated with disease progression. Results: Islet autoantibody-positive children with a genetic risk score in the lowest quartile had a slower progression from single to multiple autoantibodies (p=0.018), from single autoantibodies to diabetes (p=0.004), and by trend from multiple islet autoantibodies to diabetes (p=0.06). In a Cox proportional hazards analysis, faster progression was associated with an increased genetic risk score independently of HLA genotype (HR for progression from multiple autoantibodies to type 1 diabetes, 1.27, 95% CI 1.02 to 1.58 per unit increase), an earlier age of islet autoantibody development (HR, 0.68, 95% CI 0.58 to 0.81 per year increase in age) and female sex (HR, 1.94, 95% CI 1.28 to 2.93). Conclusions: Genetic risk scores may be used to identify islet autoantibody-positive children with high-risk HLA genotypes who have a slow rate of progression to subsequent stages of autoimmunity and type 1 diabetes.
  • Bonifacio, Ezio, et al. (författare)
  • An Age-Related Exponential Decline in the Risk of Multiple Islet Autoantibody Seroconversion During Childhood
  • 2021
  • Ingår i: Diabetes Care. - : American Diabetes Association. - 1935-5548.
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVE: Islet autoimmunity develops before clinical type 1 diabetes and includes multiple and single autoantibody phenotypes. The objective was to determine age-related risks of islet autoantibodies that reflect etiology and improve screening for presymptomatic type 1 diabetes.RESEARCH DESIGN AND METHODS: The Environmental Determinants of Diabetes in the Young study prospectively monitored 8,556 genetically at-risk children at 3- to 6-month intervals from birth for the development of islet autoantibodies and type 1 diabetes. The age-related change in the risk of developing islet autoantibodies was determined using landmark and regression models.RESULTS: The 5-year risk of developing multiple islet autoantibodies was 4.3% (95% CI 3.8-4.7) at 7.5 months of age and declined to 1.1% (95% CI 0.8-1.3) at a landmark age of 6.25 years (P < 0.0001). Risk decline was slight or absent in single insulin and GAD autoantibody phenotypes. The influence of sex, HLA, and other susceptibility genes on risk subsided with increasing age and was abrogated by age 6 years. Highest sensitivity and positive predictive value of multiple islet autoantibody phenotypes for type 1 diabetes was achieved by autoantibody screening at 2 years and again at 5-7 years of age.CONCLUSIONS: The risk of developing islet autoimmunity declines exponentially with age, and the influence of major genetic factors on this risk is limited to the first few years of life.
  • Bonifacio, Ezio, et al. (författare)
  • Genetic scores to stratify risk of developing multiple islet autoantibodies and type 1 diabetes : A prospective study in children
  • 2018
  • Ingår i: PLoS Medicine. - : Public Library of Science. - 1549-1676. ; 15:4
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Around 0.3% of newborns will develop autoimmunity to pancreatic beta cells in childhood and subsequently develop type 1 diabetes before adulthood. Primary prevention of type 1 diabetes will require early intervention in genetically at-risk infants. The objective of this study was to determine to what extent genetic scores (two previous genetic scores and a merged genetic score) can improve the prediction of type 1 diabetes. Methods and findings: The Environmental Determinants of Diabetes in the Young (TEDDY) study followed genetically at-risk children at 3- to 6-monthly intervals from birth for the development of islet autoantibodies and type 1 diabetes. Infants were enrolled between 1 September 2004 and 28 February 2010 and monitored until 31 May 2016. The risk (positive predictive value) for developing multiple islet autoantibodies (pre-symptomatic type 1 diabetes) and type 1 diabetes was determined in 4,543 children who had no first-degree relatives with type 1 diabetes and either a heterozygous HLA DR3 and DR4-DQ8 risk genotype or a homozygous DR4-DQ8 genotype, and in 3,498 of these children in whom genetic scores were calculated from 41 single nucleotide polymorphisms. In the children with the HLA risk genotypes, risk for developing multiple islet autoantibodies was 5.8% (95% CI 5.0%–6.6%) by age 6 years, and risk for diabetes by age 10 years was 3.7% (95% CI 3.0%–4.4%). Risk for developing multiple islet autoantibodies was 11.0% (95% CI 8.7%–13.3%) in children with a merged genetic score of >14.4 (upper quartile; n = 907) compared to 4.1% (95% CI 3.3%–4.9%, P < 0.001) in children with a genetic score of ≤14.4 (n = 2,591). Risk for developing diabetes by age 10 years was 7.6% (95% CI 5.3%–9.9%) in children with a merged score of >14.4 compared with 2.7% (95% CI 1.9%–3.6%) in children with a score of ≤14.4 (P < 0.001). Of 173 children with multiple islet autoantibodies by age 6 years and 107 children with diabetes by age 10 years, 82 (sensitivity, 47.4%; 95% CI 40.1%–54.8%) and 52 (sensitivity, 48.6%, 95% CI 39.3%–60.0%), respectively, had a score >14.4. Scores were higher in European versus US children (P = 0.003). In children with a merged score of >14.4, risk for multiple islet autoantibodies was similar and consistently >10% in Europe and in the US; risk was greater in males than in females (P = 0.01). Limitations of the study include that the genetic scores were originally developed from case–control studies of clinical diabetes in individuals of mainly European decent. It is, therefore, possible that it may not be suitable to all populations. Conclusions: A type 1 diabetes genetic score identified infants without family history of type 1 diabetes who had a greater than 10% risk for pre-symptomatic type 1 diabetes, and a nearly 2-fold higher risk than children identified by high-risk HLA genotypes alone. This finding extends the possibilities for enrolling children into type 1 diabetes primary prevention trials.
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  • Resultat 1-10 av 74
  • [1]234567...8Nästa

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