J Clin Endocrinol Metab
October 2011
Context: A strong association between autoimmune Addison's disease (AAD) and major histocompatibility complex class II-encoded HLA-DRB1-DQA1-DQB1 haplotypes is well known. Recent evidence from other autoimmune diseases has suggested that class I-encoded HLA-A and HLA-B gene variants confer HLA-DRB1-DQA1-DQB1-independent effects on disease.
Objective: We aimed to explore AAD predisposing effects of HLA-A and -B and further investigate the role of MICA and HLA-DRB1-DQA1-DQB1 in a much larger material than has previously been studied.
Background: Susceptibility to celiac disease is essentially restricted to carriers of specific HLA DQA1 and DQB1 alleles. We have developed a semi-automated sequence specific primer (SSP) PCR method for clinical HLA typing and compared the test results with those from a commercial method.
Methods: Primers for each DQA1 and DQB1 allele group were included in our PCR-SSP reaction to allow differentiation of homozygous from heterozygous carriers of risk alleles.
Objective: We report here genotyping data and type 1 diabetes association analyses for HLA class I loci (A, B, and C) on 1,753 multiplex pedigrees from the Type 1 Diabetes Genetics Consortium (T1DGC), a large international collaborative study.
Research Design And Methods: Complete eight-locus HLA genotyping data were generated. Expected patient class I (HLA-A, -B, and -C) allele frequencies were calculated, based on linkage disequilibrium (LD) patterns with observed HLA class II DRB1-DQA1-DQB1 haplotype frequencies.
Background: Although human leukocyte antigen (HLA) DQ and DR loci appear to confer the strongest genetic risk for type 1 diabetes, more detailed information is required for other loci within the HLA region to understand causality and stratify additional risk factors. The Type 1 Diabetes Genetics Consortium (T1DGC) study design included high-resolution genotyping of HLA-A, B, C, DRB1, DQ, and DP loci in all affected sibling pair and trio families, and cases and controls, recruited from four networks worldwide, for analysis with clinical phenotypes and immunological markers.
Purpose: In this article, we present the operational strategy of training, classification, reporting, and quality control of HLA genotyping in four laboratories on three continents over nearly 5 years.
Objective: To determine the relative risk associated with DPA1 and DPB1 alleles and haplotypes in type 1 diabetes.
Research Design And Methods: The frequency of DPA1 and DPB1 alleles and haplotypes in type 1 diabetic patients was compared to the family based control frequency in 1,771 families directly and conditional on HLA (B)-DRB1-DQA1-DQB1 linkage disequilibrium. A relative predispositional analysis (RPA) was performed in the presence or absence of the primary HLA DR-DQ associations and the contribution of DP haplotype to individual DR-DQ haplotype risks examined.
Background: The risk for type 1 diabetes mellitus (T1DM) and celiac disease (CD) is related to human leukocyte antigen (HLA) DQA1, DQB1 and DRB1 loci. Unfortunately, HLA typing has been too difficult and costly for frequent use. Automated genotyping focused on risk alleles could provide access to HLA typing in diagnostic evaluations, epidemiological screening and contribute to preventive strategies.
View Article and Find Full Text PDFObjective: Primary adrenal insufficiency [Addison's disease (AD)] is rare, and systematic studies are few, mostly conducted on small patient samples. We aimed to determine the clinical, immunological, and genetic features of a national registry-based cohort.
Design: Patients with AD identified through a nationwide search of diagnosis registries were invited to participate in a survey of clinical features, health-related quality of life (HRQoL), autoantibody assays, and human leukocyte antigen (HLA) class II typing.
Objective: The Type 1 Diabetes Genetics Consortium has collected type 1 diabetic families worldwide for genetic analysis. The major genetic determinants of type 1 diabetes are alleles at the HLA-DRB1 and DQB1 loci, with both susceptible and protective DR-DQ haplotypes present in all human populations. The aim of this study is to estimate the risk conferred by specific DR-DQ haplotypes and genotypes.
View Article and Find Full Text PDFLarge international biobank studies can make substantial contributions to scientific research by validation of the biological importance of previous research and by identification of previously unknown causes of disease. However, regulations for patient consent that are too strict and discrepancies in national policies on informed consent might hinder progress. Therefore, establishment of common ground for ethical review of biobank research is essential.
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