Ontology highlight
ABSTRACT:
PROVIDER: PRJEB37125 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The Human leukocyte antigen (HLA) -region, especially HLA class I and II genes, plays a major role in the predisposition to autoimmune disorders. Particularly three HLA haplotypes, DRB1*03-DQA1*05-DQB1*02 (DR3-DQ2), DRB1*04:01-DQA1*03-DQB1*03:02 (DR4-DQ8) and DRB1*15-DQA1*01-DQB1*06:02 (DR2-DQ6), have an important role in many autoimmune diseases: for example, in type 1 diabetes (T1D) the DR2-DQ6 is associated with a strongly decreased T1D risk and the DR3-DQ2 and DR4-DQ8 are associated with a moderately increased T1D risk. To clarify the mechanisms behind this association, we examined genome-wide DNA methylation in CD4+ T cells and CD19+ B cells of healthy subjects homozygous either for DR3-DQ2 (n = 19), DR4-DQ8 (n = 17) or DR2-DQ6 (n = 14), and compared methylation between the genotypes. For the study, CD4+ T cells and CD19+ B cells were isolated consecutively from PBMC samples using magnetic bead separation. DNA was extracted from the cell lysates with AllPrep DNA/RNA/miRNA Universal Kit (Qiagen, Germany). Then the individual DNA samples were pooled into 11 pooled samples with 4–5 samples per pooled sample. The original 50 samples were designated pools based on age and sex to ensure that the age and sex distributions would be as similar as possible between the pooled samples. The mean age (±SD) in the three HLA-groups (DR2-DQ6, DR3-DQ2 and DR4-DQ8) were 15.0 (±8.3), 11.1 (±5.6) and 11.8 (±7.9) and their male to female ratios were 8/6, 9/10 and 11/6. Similar pooled samples were created for both the CD4+ T cell and the CD19+ B cell samples. Then DNA methylation was examined in the pooled CD4+ T cell and CD19+ B cell samples using Illumina Infinium HumanMethylation EPIC beadchip.
2024-06-20 | E-MTAB-13654 | biostudies-arrayexpress
Project description:Background. Assessment of non-HLA variants alongside standard HLA testing was previously shown to improve the identification of potential coeliac disease (CD) patients. We intended to identify new genetic variants associated with CD in the Polish population that would improve CD risk prediction when used alongside HLA haplotype analysis. Results. Association analysis using four HLA-tagging SNPs showed that, as was found in other populations, positive predicting genotypes (HLA-DQ2.5/DQ2.5, HLA-DQ2.5/DQ2.2, and HLA-DQ2.5/DQ8) were found at higher frequencies in CD patients than in healthy control individuals in the Polish population. Both CD-associated SNPs discovered by GWAS were found in the CD susceptibility region, confirming the previously-determined association of the major histocompatibility (MHC) region with CD pathogenesis. The two most significant SNPs from the GWAS were rs9272346 (HLA-dependent; localized within 1 Kb of DQA1) and rs3130484 (HLA-independent; mapped to MSH5). Specificity of CD prediction using the four HLA-tagging SNPs achieved 92.9%, but sensitivity was only 45.5%. However, when a testing combination of the HLA-tagging SNPs and the MSH5 SNP was used, specificity decreased to 80%, and sensitivity increased to 74%.
2015-10-15 | GSE65424 | GEO
Project description:Several HLA allelic variants have been associated with protection from, or susceptibility to infectious and autoimmune diseases. Here, we examined whether specific HLA alleles would be associated with different Mtb infection outcomes. We found that DQA1*03:01, DPB1*04:02, and DRB4*01:01 were signficantly more frequent in inividuals with active TB (susceptibility alleles). Furthermore, individuals who express any of the three susceptibility alleles were associated with lower magnitude of responses against Mtb antigens. We investigated the gene expression changes induced in PBMCs by Mtb lysate and a peptide pool (MTB300) in individuals with or without expression of the susceptibility alleles.
2023-03-29 | GSE207214 | GEO
Project description:Leprosy is a chronic granulomatous disease caused by infection with Mycobacterium leprae. Genetic association studies indicated that leprosy risk is strongly associated with variation within the major histocompatibility complex (MHC) region, but the full number of variants in this region has yet to be elucidated. To identify further susceptibility loci or loss of function variants for this disease, we performed fine-mapping analysis of the MHC region using a Han Chinese reference panel (n= 10,689 patients, 29,948 genetic markers) in the data sets from our previous leprosy studies. Then, a fixed-effect meta-analysis was carried out separately for Chinese (case=2,901, control=3,801) and North Chinese (case=1,983, control=2,635) participants. The meta-analysis of Chinese participants identified 10 HLA-type or amino acid variants with lower than the genome-wide significant susceptibility signal. Next, gene-by-gene step-wise conditional analysis was performed in the combined dataset of these cohorts. Finally, we identified four new independent susceptibility loci (HLA-DQA1, HLA-C, rs3129063, and rs58327373) and confirmed one previously reported locus (HLA-DRB1) that significantly associated with leprosy in the Chinese Han population. Thus the results of this study increase knowledge about leprosy risk variants and illustrate the value of HLA imputation for fine mapping of causal variants in the MHC.
2018-09-30 | GSE119367 | GEO
Project description:The dataset consists of Oxford Nanopore targeted RNA-based amplicon data of 12 classical HLA genes (HLA-A, -B, -C, -DRA, -DRB1, -DRB3, -DRB4, -DRB5, -DQA1, -DQB1, -DPA1, and DPB1) of 50 healthy individuals. The 12 classical genes were sequenced in two separate gene pools on R9.4 flowcells using MinION sequencer. Per individual, gene pool 1 contains HLA-A, -B, -C, -DRB1, -DRB3, -DRB4, -DRB5, and -DPB1 and gene pool 2 HLA-DRA, -DQA1, -DQB1, and -DPA1. The dataset includes 100 fastq files of Oxford Nanopore 2D reads (50 for gene pool 1 and 50 for gene pool 2).
| EGAD00001006814 | EGA
Project description:Meta-analysis Identifies MHC Loci in or near HLA-DRB1, HLA-DQA1, HLA-C as Associated with Leprosy in Chinese Han Population
| PRJNA488957 | ENA
Project description:Background. Rheumatic heart disease (RHD) following Group A Streptococcus (GAS) infections is heritable and prevalent in Indigenous populations. Molecular mimicry between human and GAS proteins triggers pro-inflammatory cardiac valve-reactive T-cells. Methods. Genome-wide genetic analysis was undertaken in 1263 Aboriginal Australians (398 RHD cases; 865 controls). Single nucleotide polymorphisms (SNPs) were genotyped using Illumina HumanCoreExome BeadChips. Direct typing and imputation was used to fine-map the human leukocyte antigen (HLA) region. Epitope binding affinities were mapped for human cross-reactive GAS proteins, including M5 and M6. Results. The strongest genetic association was intronic to HLA-DQA1 (rs9272622; P=1.86x10-7). Conditional analyses showed rs9272622 and/or DQA1*AA16 account for the HLA signal. HLA-DQA1*0101_DQB1*0503 (OR 1.44, 95%CI 1.09-1.90, P=9.56x10-3) and HLA-DQA1*0103_DQB1*0601 (OR 1.27, 95%CI 1.07-1.52, P=7.15x10-3) were risk haplotypes; HLA_DQA1*0301-DQB1*0402 (OR 0.30, 95%CI 0.14-0.65, P=2.36x10-3) was protective. Human myosin cross-reactive N-terminal and B repeat epitopes of GAS M5/M6 bind with higher affinity to DQA1/DQB1 alpha/beta dimers for the two risk haplotypes than the protective haplotype. Conclusions. Variation at HLA_DQA1-DQB1 is the major genetic risk factor for RHD in Aboriginal Australians studied here. Cross-reactive epitopes bind with higher affinity to alpha/beta dimers formed by risk haplotypes, supporting molecular mimicry as the key mechanism of RHD pathogenesis.
| EGAS00001002678 | EGA