N.-Y. Chen

Identification of a novel HLA-A*33:03:11 allele by polymerase chain reaction sequence-based typing in a Chinese cord blood donor.

HLA‐B*13:83 differs from HLA‐B*13:01:01 by 2 nucleotide substitutions at positions 103 and 106.

Distribution of MICB diversity in the Zhejiang Han population: PCR sequence-based typing for exons 2–6 and identification of five novel MICB alleles

The polymorphism of major histocompatibility complex class I chain-related gene B (MICB) and variations in MICB alleles in a variety of populations have been characterized using several genotyping approaches. In the present study, a novel polymerase chain reaction sequence-based typing (PCR-SBT) method was established for the genotyping of MICB exons 2–6, and the allelic frequency of MICB in the Zhejiang Han population was investigated. Among 400 unrelated healthy Han individuals from Zhejiang Province, China, a total of 20 MICB alleles were identified, of which MICB*005:02:01, MICB*002:01:01, and MICB*004:01:01 were the most predominant alleles, with frequencies of 0.57375, 0.1225, and 0.08375, respectively. Nine MICB alleles were detected on only one occasion, giving a frequency of 0.00125. Of the 118 distinct MICB ∼ HLA-B haplotypes identified, 42 showed significant linkage disequilibrium (P < 0.05). Haplotypes MICB*005:02:01 ∼ B*46:01, MICB*005:02:01 ∼ B*40:01, and MICB*008 ∼ B*58:01 were the most common haplotypes, with frequencies of 0.0978, 0.0761, and 0.0616, respectively. Five novel alleles, MICB*005:07, MICB*005:08, MICB*027, MICB*028, and MICB*029 were identified. Compared with the MICB*005:02:01 sequence, a G > A substitution was observed at nucleotide position 210 in MICB*005:07, and a 1,134 T > C substitution in MICB*005:08 and an 862 G > A substitution in MICB*027 were detected. In addition, it appears that MICB*028 probably arose from MICB*004:01:01 with an A to G substitution at position 1,147 in exon 6. MICB*029 had a G > T transversion at nucleotide position 730 in exon 4, compared with that of MICB*002:01:01. On the basis of the new PCR-SBT assay, these observed results demonstrated MICB allelic variations in the Zhejiang Han population.

HLA-A, -B and -DRB1 allele and haplotype frequencies of 8333 Chinese Han from the Zhejiang province, China

The distribution of human leucocyte antigen (HLA) allele and haplotype is varied among different ethnic populations. In this study, HLA‐A, ‐B and ‐DRB1 allele and haplotype frequencies were determined in 8333 volunteer bone marrow donors of Zhejiang Han population using the polymerase chain reaction sequence‐based typing. A total of 52 HLA‐A, 96 HLA‐B and 61 HLA‐DRB1 alleles were found. Of these, the top three frequent alleles in HLA‐A, HLA‐B and HLA‐DRB1 loci, respectively, were A*11:01 (24.53%), A*24:02 (17.35%), A*02:01 (11.58%); B*40:01 (15.67%), B*46:01 (11.87%), B*58:01 (9.05%); DRB1*09:01 (17.54%),DRB1*12:02 (9.64%) and DRB1*08:03 (8.65%). A total of 171 A‐B‐DRB1 haplotypes with a frequency of >0.1% were presented and the five most common haplotypes were A*33:03‐B*58:01‐ DRB1*03:01, A*02:07‐B*46:01‐DRB1*09:01, A*30:01‐B*13:02‐DRB1*07:01, A*33:03‐B*58:01‐RB1*13:02 and A*11:01‐B*15:02‐DRB1*12:02. The information will be useful for selecting unrelated bone marrow donors and for anthropology studies and pharmacogenomics analysis.

Identification of two novel HLA-A alleles, HLA-A*03:181 and HLA-A*03:229 in Chinese individuals.

HLA‐A*03:181 and HLA‐A*03:229 differ from HLA‐A*03:01:01:01 by one and three nucleotide substitutions, respectively.

Identification of a novel HLA‐A*02:06:14 allele by polymerase chain reaction sequence‐based typing in a Chinese bone marrow donor

HLA*02:06:14 differs from HLA-A*02:06:01 by a single nucleotide substitution G > A at position 246.

HLA-A locus allelic dropout in Sanger sequence-based typing due to the single nucleotide polymorphism of exon 1.

The DNA‐based method is used widely for HLA genotyping in routine work, but some allele may be dropout in the genotyping procedure. Here, we reported a case with HLA‐A allele dropout in the Sanger PCR‐SBT test. The initial PCR‐SBT method with a commercial agent kit was not characterized, and the result of Luminex technology indicated the dropout as a HLA‐A*02 allele. Subsequently, the sequences of exons 2–4 were fully matched with the A*02:07 and A*11:01:01 by allele group‐specific primer amplification PCR‐SBT. On further analysis, a novel allele A*02:07:07 was identified, which has one nucleotide difference from A*02:07:01 at position 6 C>G of exon 1. According to the sequencing for 5′‐UTR to 3′‐UTR, the novel single nucleotide polymorphism of exon 1 was contributed to HLA‐A locus allele dropout in the sample. Our results indicated multiplatform analysis is necessary when a conclusive HLA type cannot be determined by a single methodology.

Identification of two novel alleles HLA-A*11:133 and A*11:02:05 by polymerase chain reaction sequence-based typing.

HLA-A*11:113 shows one nucleotide difference from HLA-A*11:01:01: HLA-A*11:02:05 shows a single nucleotide difference from HLA-A*11:02:01.

HLA-B allele dropout in PCR sequence-specific oligonucleotide probe typing due to intronic polymorphism in the novel B*58:01:01:02 allele

Currently, Luminex technology based on the PCR sequence‐specific oligonucleotide (SSO) probe method has been widely used for HLA genotyping in the immunogenetics laboratories. Here, we reported a case with HLA‐B allele dropout by Luminex technology. The initial HLA‐B result of the Luminex method with a commercial agent kit was inconclusive, and then, the result of PCR‐SBT technology indicated the dropout as a HLA‐B*58 allele. Subsequently, the full‐length sequence of HLA‐B allele was determined by TOPO‐TA cloning, and a novel allele B*58:01:01:02 was identified in the individual. Compared with HLA‐B*58:01:01:01, the novel allele showed some nucleotides difference at 509 C>T, 521 T>G and CCC insertion in position 503 of intron 2. According to the full‐length sequence, the new mutations of intron 2 were contributed to HLA‐B locus allele dropout in the sample. Our results indicated multiplatform should be used to improve the HLA typing accuracy when a conclusive HLA genotype cannot be determined.

Identification of the novel HLA‐B*52:42 allele by polymerase chain reaction sequence‐based typing in a Chinese bone marrow donor

HLA‐B*52:42 is different from HLA‐B*52:01:01:01 by a single nucleotide substitution at position 343G>C.

Comparison of the KIR3DS1/Bw4 distribution in Chinese healthy and acute myeloid leukemia individuals.

Killer cell immunoglobulin like receptor (KIR) 3DS1 is one of the most important activating receptors and some studies revealed that KIR3DS1 combined with HLA ligand was not related to acute myeloid leukemia (AML), but rare data was reported in Chinese population. In this study, KIR3DS1 gene polymorphisms and HLA-Bw4 were investigated in 189 Chinese AML patients compared with 166 healthy individuals. The results showed that the distributions of KIR3DS1, Bw4, 3DS1/Bw4 and 3DS1/Bw4-80I were insignificantly different between AML and healthy individuals. This study suggests that the presence of 3DS1 and HLA-Bw4 ligands have no effect on AML disease.