Search

Full genomic sequence shows HLA-G*01:19 differs from HLA-G*01:04:01:01 only at position 99 in exon 2., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

A new allelic variant in HLA-B*46:01 lineage, HLA-B*46:01:25, has been identified in a male individual of Mongol ethnicity residing in northern China. Following polymerase chain reaction-sequence-based typing (PCR-SBT), this novel variant was further confirmed by cloning, phasing and sequencing. HLA-B*46:01:25 differs from HLA-B*46:01:01 by a single synonymous T substitution at nucleotide position 137 (C - T) in exon 4, corresponding to codon 228 (ACC-ACT) of the mature HLA-B mRNA molecule., (© 2018 John Wiley & Sons Ltd.)

In this study, the 5'promoter region of MHC class I chain-related gene A (MICA) was investigated in 104 healthy, unrelated Han individuals recruited from northern China, using PCR-sequencing method. Twelve variable sites were detected, which were in very strong linkage disequilibrium with each other. Twelve different MICA 5'promoter haplotypes were identified, among which Promoter-7 predominated (0.5529). Twenty-six extended haplotypes incorporating MICA 5'promoter and MICA exons 2-5 were observed in this population, 9 of which were in significant linkage disequilibrium (LD). Phylogenetic analysis of 5'promoter refined MICA sub-lineage structure previously constructed according to MICA coding and 3'untranslated regions. Ewens-Watterson homozygosity statistics at MICA 5'promoter region were consistent with neutral expectations. None of the five variable sites detected within the minimal promoter of MICA gene was located in the putative binding sites for transcription factor. Our study provided for the first time the sequence information about 5'promoter of MICA gene at a human population level. The data will facilitate the understanding of regulation of MICA gene expression, which represents a promising pathway for immune intervention against cancer, autoimmune disorders and infections., (Copyright © 2013 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

Major histocompatibility complex class I chain-related gene B (MICB) has only been characterized for allelic variation in very few human populations. The MICB polymorphism remains largely unknown in Chinese populations. In this study, 104 healthy unrelated Han subjects recruited from central Inner Mongolia Autonomous Region, northern China, were investigated by sequence-based typing for MICB allelic variation, the association of MICB alleles with AluyMICB insertion/deletion dimorphism located in MICB intron 1, linkage disequilibrium of MICB with human leukocyte antigen (HLA)-B and MICA, and HLA-A-C-B-MICA-MICB haplotypic diversity. Ten kinds of MICB alleles were observed, among which MICB*005:02/010, MICB*002:01, and MICB*004:01 were the most frequent alleles with frequencies of 51.44, 16.35, and 11.54%, respectively. Significant linkage disequilibrium (LD) was observed for 9 of the 21 HLA-B-MICB haplotypes and 6 of the 17 MICA-MICB haplotypes with a frequency >1.5%. In particular, HLA-B*13:01 and HLA-B*13:02, both of which were frequently represented in this population, exhibited a distinct LD pattern with the MICB allele. A new MICB allele, MICB*023, was identified, which differed from MICB*005:02/010 by a single mutation of G to A at position 86 in exon 2, resulting in an amino acid change from arginine to histidine at codon 6. HLA-A*30-C*06-B*13:02-MICA*008:01-MICB*005:02/010 was the most common haplotype, with a frequency of 8.64% in this population. HLA-A*02-C*08-B*48-MICA*Del-MICB*009N demonstrated a frequency of 2.4% in this population. Our results provide for the first time data regarding the MICB genetic polymorphism in northern Chinese Han populations and will form the basis for future studies of the potential role of MICB in allogeneic organ transplantation and disease association in related ethnic groups., (Copyright © 2011 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

The association between ALOX5AP SG13S114 polymorphism and ischemic stroke (IS) susceptibility has extensively been investigated, especially in white populations; however, the results were inconclusive. Here, we perform a meta-analysis to clarify the effect of SG13S114 variant on the IS risk in Europeans. The Web of Science, PubMed, EMBASE, and Medline were searched up to August 1st, 2016. Data were extracted and the odd ratios (ORs) and 95% confidence intervals (CIs) were calculated by a fixed-effects or random-effects model. In total, 8 case control studies involved 8062 subjects were finally included in this meta-analysis. We observed a significantly decreased IS risk in persons carrying an A allele at the SG13S114 polymorphism compared with those with a T allele (A vs T, OR = 0.856, 95% CI = 0.797-0.919, p < 0.001). In addition, the results of sensitivity and cumulative meta-analysis indicated the robustness of our results. In addition, the publication bias was not detected using the funnel plot and Egger's tests. In summary, the present meta-analysis suggested that the A allele at the ALOX5AP SG13S114 polymorphism is a protective factor for the IS in the Europeans. In addition, further studies with large sample size are needed to validate the association, as well as in other ethnic groups. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we investigated the major histocompatibility complex (MHC) class I chain-related gene B (MICB) allelic variation by sequence-based typing (SBT) in 201 healthy, unrelated Han subjects from Hunan province, southern China. Eleven MICB alleles were observed, among which MICB∗005:02 predominated with a frequency of 64.93%. Significant linkage disequilibrium (LD) was observed for 5 HLA-B-MICB and 6 MICA-MICB haplotypes. Compared with a northern Chinese Han population, several MICB-containing haplotypes appeared to be highly specific to this southern Chinese Han population. Two new MICB alleles, MICB∗005:06 and MICB∗026, were identified. Aligned with MICB∗005:02, MICB∗005:06 has a synonymous T replacement at nucleotide 762 in exon 4; MICB∗026 has probably arisen from MICB∗004:01 through a single nucleotide substitution from G to A at position 826 in exon 4, leading to an amino acid change from glutamic acid to lysine at codon 253. HLA-A∗02-C∗01-B∗46-MICA∗010-MICB∗005:02-DRB1∗09 was the most prevalent six-locus haplotype with a frequency of 8.49%. HLA-A∗30-C∗06-B∗13:02-MICA∗008:01-MICB∗005:02-DRB1∗07 appeared to be a conserved extended haplotype. Our results provide new information about MICB genetic polymorphism in Chinese Han populations, and will inform future studies of the potential role of MICB in allogeneic organ transplantation and disease susceptibility in related ethnic groups. [Copyright &y& Elsevier]