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Background An erythroid cell-specific regulatory element (+5·8-kb) in the first intron of ABO is responsible for the antigen differential expression and the regulatory activity of the element was affected by the nucleotide mutation in the +5·8-kb region. Currently, many individuals with ABO subgroups were found in the Chinese population, but there was little information about the function of +5·8-kb region in these individuals. Here, we studied the mechanism of the mutation in the +5·8-kb region responsible for reducing of antigen expression in 30 ABO subtype Chinese individuals without mutation in the coding region or splicing site. Materials and methods The nucleotide sequence of the partial intron 1 covering the +5·8-kb site was amplified and directly sequenced. The haplotype with the novel mutation was obtained by the TOPO TA cloning. Both of the ABO promoter and the +5·8 kb regulatory element were subcloned into the basic luciferase reporter plasmid using the double endonuclease digestion. The promoter activity was examined by the dual-luciferase report vector with K562 cells. Results A novel nucleotide substitution +5904 C>T located at RUNX1-binding site in the +5·8 kb site was identified from three individuals with B subtypes. +5890 T>G were found in three Bel and one Ael phenotypes. Cotransfection and luciferase assays demonstrated that the +5904 C>T could obviously reduce activity of the +5·8 kb site. Conclusion The study suggested that the transcriptional activity of the +5·8 kb site could be downregulated by the single point mutation of RUNX1 motif, leading to reduction in A or B antigen expression.

Deletion of major histocompatibility complex class I chain-related genes A (MICA*Del) was investigated in 3,411 DNA samples from two southern Chinese Han populations (Hunan Han, HNH; Guangdong Han, GDH), two northern Chinese populations (Inner Mongolia Han, IMH; Inner Mongolia Mongol, IMM) and one southeastern Chinese Han population (Fujian Han, FJH) using an in-house polymerase chain reaction-sequence specific priming (PCR-SSP) assay, which enables direct discrimination between heterozygote and homozygote for MICA*Del. MICA*Del showed a frequency ranging from 0.8% in FJH to 5.7% in IMM (Pcorrected < 0.05), indicating northward increase in frequency of MICA*Del in Chinese populations. In contrast to the association reported recently in a Taiwan Chinese population and a Malaysian Chinese cohort, MICA*Del distribution did not differ between 1,120 patients with nasopharyngeal carcinoma (NPC) and 1,483 normal controls in the HNH population (1.03% in NPC cases vs 1.18% in the controls, OR (95% CI) = 0.87 (0.51-1.47), p = 0.69). Further gender-stratified analysis also failed to disclose any male-specific association reported in a Taiwan Chinese population. Multi-locus typing of the 94 samples carrying MICA*Del revealed two new haplotypes, HLA-A*11:01-B*13:01-MICA*Del-MICB*009N-DRB1*04:06 and HLA-B*35:01-MICA*Del-MICB*009N-DRB1*15:01, in addition to HLA-B*48-MICA*Del. Unexpectedly, two samples with MICA*Del in the HNH population were each consistently found to have two distinct MICA alleles, indicating the existence of two MICA gene copies on certain HLA haplotypes. Based on the results from a sizeable case-control study, our data suggest that there is no association between MICA*Del and NPC in the southern Chinese Han population.

In this study, polymorphisms of major histocompatibility complex class I chain-related genes A and B (MICA and MICB) and human leucocyte antigen (HLA)-B gene were investigated for 158 unrelated Chinese Mongolian subjects recruited from central Inner Mongolia Autonomous Region, northern China, by polymerase chain reaction-sequence-based typing (PCR-SBT) and cloning. Collectively, 79 alleles, including 20 MICA, 12 MICB and 47 HLA-B alleles, were identified. MICA*008:01 (21.2%), MICB*005:02 (48.1%) and HLA-B*51:01 (7.91%) were the most common alleles. Significant global linkage disequilibrium (LD) was detected between HLA-B and MICA, HLA-B and MICB, and MICA and MICB loci (all P

HLA-B*40:338N differs from HLA-B*40:01:01 by a single nucleotide substitution at position 843C>A.

A new MICA allelic variant, MICA*007:07, was identified in an individual of Mongol ethnicity in the Inner Mongolia Autonomous Region, northern China. Following polymerase chain reaction-sequence-based typing (PCR-SBT), this new allele was further confirmed by cloning and sequencing. MICA*007:07 differs from MICA*007:01 by a synonymous mutation from G to A at the 2nd nucleotide position in exon 2. MICA*007:07 was linked to HLA-B*27:05.

HLA-B*55:02:09 and HLA-B*55:80 differ from HLA-B*55:02:01 by 1 single nucleotide substitution, respectively.

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.

A novel allelic variant in HLA-B*40 lineage, HLA-B*40:298:02, has been identified in an individual of Han ethnicity afflicted with nasopharyngeal carcinoma in Hunan province, southern China. Following polymerase chain reaction-Sanger sequence-based typing (PCR-SBT), this new variant was further confirmed by two distinct strategies of cloning and sequencing. HLA-B*40:298:02 differs from HLA-B*40:298:01 by a single synonymous cytosine substitution at nucleotide position 26 (T→C) in exon 3, which corresponds to codon 99 of the mature HLA-B mRNA molecule. This new allele has an estimated frequency of 0.0002, in about 2,500 sequence-based typed subjects from the same population.

In this study, we typed 930 cases of nasopharyngeal carcinoma (NPC) and 1134 normal controls recruited from Hunan province, southern China for human leukocyte antigen-A (HLA-A) locus by sequencing exons 2-4. Very significant associations between HLA-A*02:07, HLA-A*11:01 and NPC were established [25.7% vs 16.18%; odds ratio, OR (95% confidence interval, CI) = 1.79 (1.54-2.09), P < 0.0001 and 21.1% vs 30.42%, OR (95% CI) = 0.61 (0.53-0.70), P

KIR2DL2 and KIR2DL3 are important inhibitory receptors that recognize a subset of HLA-C allelic products carrying Ser77 and Asn80. In this study, we have determined KIR2DL2 and KIR2DL3 diversity in the Chinese Han population by a PCR sequence-based typing. Based on sequencing, the coding regions of 166 Chinese Han individuals, seven new polymorphic sites (238G>A, 405G>A, 476A>G, 550G>A, 608G>A, 789T>C, 947T>C) were found. KIR2DL2*00301, *00101, KIR2DL3*00101,*00201,*013, *015 and ten new KIR2DL3 variants (KIR2DL3*00105, 00106, 00107, 00108, 019, 020, 021, 022, 023 and 024) were identified, of which KIR2DL3*00101 was the most frequent allele. Compared with the sequences of KIR2DL3*00101, all sequences of 2DL3*00105, 2DL3*00106, 2DL3*00107 and 2DL3*00108 had one nucleotide substitution(789T>C, 261C>T, 489G>A and 405G>A),but none resulted in amino acid change. An A>G substitution was observed in nucleotide position 476 in 2DL3*019, 608 G>A in 2DL3*020, 824T>C in 2DL3*021 and 238 G>A in 2DL3*023. In addition, 2DL3*022 probably arose from 2DL3*00201 with a nucleotide substitution G>A at 550. There were more HLA-C1 positive individuals than HLA-C2. In conclusion, the data of allelic polymorphism for KIR2DL2 and KIR2DL3 were obtained in the Chinese Han population and ten novel KIR2DL3 alleles were identified.

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

HLA-B*55:70 has one base substitution at position 199 C>T in exon 2 compared to HLA-B*55:02:01.

HLA-B*54:34 is different from HLA-A*54:01:01 by a single nucleotide substitution at position 343 G>A.

HLA-C*07:530 differs from HLA-C*07:02:01 by a single nucleotide at position 363GC.

HLA-B*27:04:06 differs from HLA-B*27:04:01 by a single-nucleotide substitution at position 396 C A.

A novel HLA-B*39:01:01-related variant, HLA-B*39:130, has been identified in a normal individual of Han ethnicity in Hunan province, southern China. Following Sanger polymerase chain reaction-sequence-based typing (PCR-SBT), this new allele was further confirmed by cloning, phasing and sequencing. Aligned with HLA-B*39:01:01, HLA-B*39:130 has a nonsynonymous thymine substitution at nucleotide position 94 in exon 4, resulting in amino acid change from threonine to isoleucine at codon 214 (ACA→ATA) of the mature HLA-BmRNA molecule.

HLA-B*27:147 differs from HLA-B*27:04:01 by a single nucleotide substitution at position 523 CG.

HLA-DRB1*15:127 has 1 nucleotide change from HLA-DRB1*15:01:01:01 at position 308 CG.

HLA-B*40:01:41 differs from HLA-B*40:01:01 by a single nucleotide substitution at position 195 GA.

HLA-B*55:02:09 and HLA-B*55:80 differ from HLA-B*55:02:01 by 1 single nucleotide substitution, respectively.

HLA-B*52:01:27 differs from HLA-B*52:01:01 by a single nucleotide substitution at position 681 CT.

HLA-C*01:109N differs from HLA-C*01:02:01 by a single nucleotide substitution at position 683 G > A.

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-A*02:625 differs from HLA-A*02:06:01:01 by a single nucleotide substitution at position 806 C>T.

HLA-B*40:333 differs from HLA-B*40:01:01 by a single nucleotide substitution at position 380 T>C.

HLA-DQB1*06:209 has one nucleotide change from HLA-DQB1*06:01:01 at position 260 G>C in exon 2.

Compared with HLA-DQB1*03:03:02:01, HLA-DQB1*03:03:08 and DQB1*03:03:13 have 330 G>C and 349 T>C changes, respectively.

HLA-A*02:07:06 shows 285 A>C and HLA-A*02:426 has 763 G>A change compared with HLA-A*02:07:01.

Allelic polymorphism and expression variation of killer cell immunoglobulin-like receptor (KIR) 3DL1 on natural killer (NK) cells differ among populations. To determine whether the phenotypic variants are due to KIR polymorphism, transcription or copy number, the allelic polymorphism, mRNA levels and antigen expression of KIR3DL1 were assessed in 162 individuals. We characterized 13 KIR3DL1 alleles, five of which were novel. In addition, 21 genotypes were identified. The correlation between the binding patterns of NK cells to anti-KIR3DL1 and KIR3DL1 alleles was also examined. NK cells with different 3DL1 alleles showed distinct binding levels to anti-KIR3DL1. The binding frequencies of NK cells to anti-KIR3DL1 were not accordant with their binding levels, but both associated with the allele copy numbers. The mRNA expression amounts of individuals with two copy alleles were higher than those of individuals with one copy allele. Our data indicate that both the allele copy number and polymorphism of KIR3DL1 influence the antigen expression on the NK-cell surface, but only the copy number was associated with mRNA expression.

HLA-C*08:128 shows a substitution C to T at position 704 when compared to HLA-C*08:01:01.

HLA-DRB1*08:69 has one nucleotide change from HLA-DRB1*08:03:02 at position 262 GA.

BACKGROUND AND OBJECTIVES Human platelet alloantigen (HPA) genotyping is important for the diagnosis and prevention the alloimmune platelet disorders. In this study, a simultaneous genotyping method for HPA-1 to -28bw systems was established using multiplex PCR-SBT and the frequencies of genotypes and alleles of HPA-1 to -28bw systems in the Zhejiang Han population were analysed. MATERIALS AND METHODS The specific primers were designed according to the nucleotide sequences of HPA-1 to 28bw systems which are located in ITGB3, GP1BA, ITGA2B, ITGA2, GP1BB and CD109, respectively. The multiplex PCR amplification systems were used, and then, the amplicons were purified and sequenced. A total of 335 healthy volunteer blood donors were detected. RESULTS The genotypes of ten reference samples from Platelet Immunology Workshop of ISBT were in concordance with the known genotypes. Among the 28 HPA systems, HPA a and b alleles were found in HPA-1 to 6w, HPA-15 and HPA-21w systems in the Chinese Han population, while only HPA aa genotype was detected in the other HPA systems. The frequencies of HPA-1a and HPA-1b were 0·993 and 0·007, with 0·943 and 0·057 for HPA-2a and HPA-2b, 0·527 and 0·473 for HPA-3a and HPA-3b, 0·997 and 0·003 for HPA-4a and HPA-4b, 0·991 and 0·009 for HPA-5a and HPA-5b, 0·980 and 0·020 for HPA-6wa and HPA-6wb, 0·508 and 0·492 for HPA-15a and HPA-15b and 0·994 and 0·006 for HPA-21wa and HPA-21wb. CONCLUSIONS One multiplex PCR-SBT method for HPAs was established and the data of the study could help to prevent and treat for alloimmune thrombocytopenia.

HLA-B*39:97N differs from HLA-B*39:01:01 by a two nucleotide insertion at position 604-605.

HLA-B*39:01:23 differs from HLA-B*39:01:01 by a single nucleotide substitution at position 153 CT.

The KIR2DL2*00103 allele is different from KIR2DL2*00101 by a single nucleotide substitution at position 996 CT.

HLA-DRB1*12:50 is different from HLA-DRB1*12:02:01 by a single nucleotide substitution at position 320 AC.

HLA-B*52:42 is different from HLA-B*52:01:01:01 by a single nucleotide substitution at position 343GC.

HLA-A*02:543 differ from HLA-A*02:12 by two nucleotide substitutions.

HLA-B*13:98 differs from HLA-B*13:02:01 by a single nucleotide substitution at position 193 A>G.

Summary Recently, four new platelet alloantigen (HPA) systems HPA-18w to-21w were identified. However, genotyping for HPA-18w to -21w alleles was rarely reported. Here, we established a polymerase chain reaction sequence–based typing (PCR-SBT) method and investigated the distribution of HPA-18w to -21w alleles in the Chinese Han population. The specific primers of HPA-18w, -19w, -20w and -21w were designed, and the PCR products were bidirectionally sequenced. 855 randomly selected platelet donors were genotyped for HPA-18w to -21w with the PCR-SBT method. The results showed that all individuals were monomorphic for HPA-18w to HPA-20w with a/a homozygous frequency of 1.0 and absence of HPA-18bw to -20bw alleles. The frequencies of the HPA-21a/21a and HPA-21a/21b genotypes were 0.981(839/855) and 0.019(16/855), respectively. Seven mutations were confirmed on sequenced region separate from HPA polymorphisms, including ITGA2 (IVS17+48G>A and IVS17+72G>A), ITGA2B (IVS19-26C>G) and ITGB3 (IVS4+234C>T, IVS11-19 T>C, IVS11-104T>C and GT repeats from IVS11-131 to IVS11-109). These data will provide useful information for diagnosis, prevention and treatment of alloimmune thrombocytopaenia.

Surface plasmon polaritons (SPPs) on metal surfaces corrugated periodically with shallow grooves are theoretically investigated in terahertz (THz) frequency range. Different geometrics of the grooves are analyzed, and it is found that SPPs on the surface with the trapeziform grooves have the best field confinement. The influence of the absorption of metal at THz frequencies on the performance of spoof SPPs is also examined. It is shown that long propagation length and subwavelength field confinement are simultaneously available for SPPs on the structured surface with trapeziform grooves. Metal surfaces with such a structure may lead to a new design of devices for routing terahertz radiations.

HLA-DQB1*03:181 has one nucleotide change from HLA-DQB1*03:05:01 at position 470CG.

HLA-B*27:147 differs from HLA-B*27:04:01 by a single nucleotide substitution at position 523 C>G.

HLA-B*52:01:27 differs from HLA-B*52:01:01 by a single nucleotide substitution at position 681 C>T.

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

HLA-DQB1*05:15 differs from DQB1*05:03:01:01 by a single nucleotide substitution at codon 80 (AGA>AAA).

HLA-B*55:70 has one base substitution at position 199 CT in exon 2 compared to HLA-B*55:02:01.

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