Search

HLA-DRB1*04:316 differs from HLA-DRB1*04:03:01:01 by one nucleotide substitution at position 161 in exon 2.

McLeod syndrome is a rare XK gene-related progressive, debilitating disease involving multiple systems. The blood group phenotypes in McLeod syndrome patients usually display the Kx antigen loss and a decrease in the Kell blood group system antigen expression. This paper describes a 41-year-old male Chinese patient with McLeod syndrome. He first attended a hospital in 2015 and developed progressively worsening symptoms 4 years ago. As the disease progressed, the patient exhibited memory loss, unresponsiveness, and chorea and displayed elevated creatine kinase levels. However, McLeod syndrome could not be diagnosed by these signs and laboratory results. The patient was readmitted to the hospital in 2020 and was suspected of having McLeod syndrome. Serological analysis of the Kell blood group system and genotyping for the XK blood group system were performed, revealing the weak expression of the K antigen and the negative K antigen. Sequencing of the coding region of the XK gene showed a hemizygous c.942G>A variation in the XK gene, which resulted in a premature stop codon at position 314 (p.Trp314Ter). Therefore, the patient was diagnosed with McLeod syndrome. In conclusion, this paper presents a case of McLeod syndrome caused by a nonsense variation c.942G>A in the XK gene. The analysis of the XK gene and blood group antigen is helpful for the diagnosis of McLeod syndrome and for distinguishing it from many other diseases.

To explore the molecular mechanism for an individual with Bweak subtype.Serological methods were used to identify the proband's phenotype. In vitro enzyme activity test was used to determine the activity of B-glycosyltransferase (GTB) in her serum. The genotype was determined by PCR amplification and direct sequencing of exons 5 to 7 and flanking sequences of the ABO gene. T-A cloning technology was used to isolate the haploids. The primary physical and chemical properties and secondary structure of the protein were analyzed with the ProtParam and PSIPRED software. Three software, including PolyPhen-2, SIFT, and PROVEAN, was used to analyze the effect of missense variant on the protein.Serological results showed that the proband's phenotype was Bweak subtype with anti-B antibodies presented in her serum. In vitro enzyme activity assay showed that the GTB activity of the subject was significantly reduced. Analysis of the haploid sequence revealed a c.398TC missense variant on the B allele, which resulted in a novel B allele. The 398TC variant has caused a p.Phe133S substitution at position 133 of the GTB protein. Based on bioinformatic analysis, the amino acid substitution had no obvious effect on the primary and secondary structure of the protein, but the thermodynamic energy of the variant protein has increased to 6.07 kcal/mol, which can severely reduce the protein stability. Meanwhile, bioinformatic analysis also predicted that the missense variant was harmful to the protein function.The weak expression of the Bweak subtype may be attributed to the novel allele of ABO*B.01-398C. Bioinformatic analysis is helpful for predicting the changes in protein structure and function.

Compared with HLA-C*01:02:01:01, the alleles HLA-C*01:02:73 and HLA-C*01:02:75 each show one single nucleotide substitution respectively.

HLA-B*46:83 differs from HLA-B*46:03 by one single nucleotide substitution at position 539GT.

HLA-DPB1*03:01:14 differs from HLA-DPB1*03:01:01:01 by a single nucleotide substitution at position 390 C A.

HLA-A*24:02:138 differs from HLA-A*24:02:01:01 by one nucleotide substitution at position 549 CT.

In order to treat the alloimmunization platelet transfusion refractoriness (PTR), human leukocyte antigen (HLA)-type and/or human platelet antigen (HPA)-type matched platelets between donors and patients are usually used. Therefore, genotyping of HLA-A and HLA-B loci, as well as HPA systems, for donors and patients, is of great significance. However, there is a rare report of genotyping for HLA-A and HLA-B loci as well as HPA systems at the same time. In this study, a high-throughput method for simultaneous genotyping of HLA-A and HLA-B loci, as well as HPA genotyping, was developed. A RNA capture probe panel was designed covering all exon sequences of the GP1BA, GP1BB, ITGA2, CD109, ITGB3, and ITGA2B genes and HLA-A and HLA-B loci. The HLA-A, HLA-B, and 34 HPA systems were genotyped using a targeted next-generation sequencing (NGS) method. The genotypes of the HLA-A and HLA-B loci, as well as the HPA, were assigned based on the nucleotides in the polymorphism sites. Using the NGS method, 204 unrelated blood specimens were successfully genotyped for all 34 HPA systems as well as HLA-A and HLA-B loci. The accuracy of the NGS method was 100%. Only HPA-2, HPA-3, HPA-5, HPA-6w, HPA-15, and HPA-21w showed polymorphism with frequencies of 0.9412, 0.6863, 0.9853, 0.9779, 0.4314, and 0.9951 for a allele, respectively. Thirty-two single nucleotide variants (SNVs) were detected. Of them, 12 SNVs can lead to amino acid change. HLA-A*11:01 and HLA-B*46:01 are the most common alleles for HLA-A and HLA-B loci. A targeted next-generation sequencing method for simultaneously genotyping HPA systems and HLA-A and HLA-B loci was first established, which could be used to create a database of HLA-typed and/or HPA-typed unrelated donors.

HLA-B*50:01:17 shows one nucleotide substitution at position 861 when compared with HLA-B*50:01:01:01.

HLA-A*01:348 differs from HLA-A*01:01:01:01 by a single nucleotide substitution at position 140 T C.

HLA-A*24:520 differs from HLA-A*24:02:01:01 by one nucleotide substitution at position 668 C→T in exon 4.

Compared with HLA-DRB1*11:01:01:01, the alleles HLA-DRB1*11:262 and HLA-DRB1*11:268 each show one nucleotide substitution.

Killer cell immunoglobulin‐like receptors (KIRs) interact with polymorphic human leucocyte antigen (HLA) class I molecules, modulating natural killer (NK) cell functions and affecting both the susceptibility and outcome of immune‐mediated diseases. The KIR locus is highly diverse in gene content, copy number and allelic polymorphism within individuals and across geographical populations. To analyse currently under‐represented Asian and Pacific populations, we investigated the combinatorial diversity of KIR and HLA class I in 92 unrelated Malay and 75 Malaysian Chinese individuals from the Malay Peninsula. We identified substantial allelic and structural diversity of the KIR locus in both populations and characterized novel variations at each analysis level. The Malay population is more diverse than Malay Chinese, likely representing a unique history including admixture with immigrating populations spanning several thousand years. Characterizing the Malay population are KIR haplotypes with large structural variants present in 10% individuals, and KIR and HLA alleles previously identified in Austronesian populations. Despite the differences in ancestries, the proportion of HLA allotypes that serve as KIR ligands is similar in each population. The exception is a significantly reduced frequency of interactions of KIR2DL1 with C2(+)HLA‐C in the Malaysian Chinese group, caused by the low frequency of C2(+)HLA. One likely implication is a greater protection from preeclampsia, a pregnancy disorder associated with KIR2DL1, which shows higher incidence in the Malay than in the Malaysian Chinese. This first complete, high‐resolution, characterization of combinatorial diversity of KIR and HLA in Malaysians will form a valuable reference for future clinical and population studies.

Background The amino acid substitutions caused by ABO gene variants are usually predicted to impact the glycosyltransferase function. Here, the effect of an amino acid substitution in the vicinity of the catalytic active region of the B-glycosyltransferase was explored in vitro and in silico study, which is important for further recognizing the ABO subgroup. Methods The ABO serological tests were performed by the routine methods. The ABO genotype was analyzed by polymerase chain reaction and sequenced bidirectionally. The haplotype of the variant allele was separated using single-strand amplification and sequencing with allele-specific primers. Stably expression cell lines with variant were constructed for study in vitro. 3D structure of the B-glycosyltransferase (GTB) variant was simulated by PyMOL software. The free energy change (ΔΔG) was calculated by FoldX. Results A variant c.737A > G was identified in a Chinese individual with Bweak phenotype, which led to an amino acid substitution p.Y246C in the vicinity of the catalytic active region of GTB enzyme. The stably expression cell lines with variant and wild type were successfully established and showed that the variant caused a decrease in protein levels and/or enzyme activity. The 3D structural of the GTB modelling found the amino acid substitution p.Y246C caused the hydrogen bond of the protein changes. Meanwhile, the free energy change (ΔΔG) value predicted the destabilizing effect on the variant GTB. Discussion The p.Y246C variant in the vicinity of the enzyme active centre reduced the antigen expression because of greatly destabilizing effect on the GTB variant.

The sequences of HLA-DRB1*14:54:09 and HLA-DRB1*14:54:10 differ from HLA-DRB1*14:54:01:01 by one single nucleotide substitution, respectively. This article is protected by copyright. All rights reserved.

In order to treat the alloimmunization platelet transfusion refractoriness (PTR), human leukocyte antigen (HLA)-type and/or human platelet antigen (HPA)-type matched platelets between donors and patients are usually used. Therefore, genotyping of

HLA-DQB1*04:85 differs from HLA-DQB1*04:02:01:01 by a single nucleotide substitution at position 629 CG.

HLA-B*51:01:83 differs from HLA-B*51:01:01:01 by one single nucleotide substitutions in exon 5.

To detect loss of heterozygosity (LOH) at human leukocyte antigen (HLA) loci in a Chinese patient with leukemia after haploidentical hematopoietic stem cell transplantation.HLA genotyping was carried out on peripheral blood, hair follicle and buccal swab samples derived from the patient after the transplantation as well as peripheral blood samples from his parents by using PCR-sequence specific oligonucleotide probe method and PCR-sequence based typing method. Short tandem repeat (STR) loci were detected by using a 23 site STR assay kit and a self-developed 6 STR loci assay for the HLA regions.After the transplantation, the HLA genotype of the peripheral blood sample of the patient was identical to his father. The patient was HLA-A*02:01,24:02, C*03:03,03:04, B*13:01,15:01, DRB1*08:03,12:02, DQB1*03:01,06:01 for his hair follicle specimen. However, homozygosity of the HLA loci was found in his buccal swab sample. Only the HLA-A*24:02-C*03:03-B*15:01-DRB1*08:03-DQB1*06:01 haplotype from his father's was present, while the HLA-A*02:01-C*03:04-B*13:01-DRB1*12:02-DQB1*03:01 haplotype from his mother was lost. After the transplantation, the alleles of the 23 STR sites in the patient's peripheral blood sample were consistent to his father, with no allelic loss detected in his buccal swab sample. However, at least 4 STR loci in the HLA region were lost in his buccal swab sample.LOH at the HLA loci has been detected in the buccal swab sample of a patient with leukemia who received haploidentical hematopoietic stem cell transplantation.

HLA-DRB1*04:05:23 differs from HLA-DRB1*04:05:01:01 by a single nucleotide substitution at position 234 G A.

Compared with HLA-B*46:01:01:01, the alleles HLA-B*46:80 and HLA-B*46:81 each show one nucleotide substitution, respectively.

HLA-DRB1*11:271 differs from HLA-DRB1*11:01:01:01 by a single nucleotide substitution at position 610G > A.

HLA-DRB1*04:305 differs from HLA-DRB1*04:05:01:01 by two nucleotide substitutions.

Compared with HLA-DQB1*05:02:01:01, the alleles HLA-DQB1*05:239 and HLA-DQB1*05:250 each show one single nucleotide substitution. This article is protected by copyright. All rights reserved.

HLA-DRB1*08:03:12 differs from HLA-DRB1*08:03:02 by a single nucleotide substitution at position 702CT.

HLA-DPB1*1273:01 differs from HLA-DPB1*05:01:01:01 by two nucleotide substitutions in exon 1.

Compared with HLA-DRB1*15:01:01:01, the alleles HLA-DRB1*15:01:43 and HLA-DRB1*15:01:44 each show one nucleotide substitution respectively.

HLA-DRB1*12:02:11 differs from HLA-DRB1*12:02:01:01 by a single nucleotide substitution at position 579 T G.

Infection with syphilis is still a major public health problem. The precise data for syphilis seroprevalence in the populations will help to develop a strategy for prevention and treatment of it. However, the data for syphilis prevalence in continuous years among volunteer blood donors in China is rare.A retrospective study forA total of 992,646 volunteer blood donors were analyzed and the positive rate of TP antibody in the blood donors was 0.43%. From 2010 to 2019, the positive rates of TP antibody were 0.53%, 0.51%, 0.51%, 0.43%, 0.36%, 0.18%, 0.11%, 0.12%, 0.11%, and 0.10%, respectively. The positive rates of TP antibody were significantly different among blood donor age group (The syphilis seroprevalence is low in the blood donors of the Hangzhou area, and the positive rate of blood donors is associated with age, educational level, and times of blood donation. Increasing the number of repeat blood donations is helpful to improve blood safety.

Compared with HLA-A*11:01:01:01, the alleles HLA-A*11:383N, and HLA-A*11:388N each show one single nucleotide substitution.

Compared with HLA-A*24:02:01:01, the alleles HLA-A*24:02:129 and HLA-A*24:02:135 each show one nucleotide substitution, respectively.