Allelic diversity of KIR2DL4 gene and identification of five novel alleles among southern Han Chinese population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the polymorphisms of the KIR2DL4 gene in a southern Han Chinese population.</p><p><b>METHODS</b>Genomic DNA isolated from 306 unrelated individuals was amplified by using KIR2DL4-specific PCR primers. The PCR products were genotyped for the entire coding sequence by sequencing-based typing (SBT). Assignment of allelic profile was accomplished with an Assign 3.5 software. For samples with inconclusive SBT results, the RT-PCR products covering the entire coding sequence of the KIR2DL4 gene were subjected to cloning and haplotype sequencing.</p><p><b>RESULTS</b>Among the 306 individuals, 11 alleles were detected, of which 5 novel alleles were officially named by the KIR subcommittee of the World Health Organization Nomenclature Committee for factors of HLA system. The observed frequencies for the 11 alleles were KIR2DL4 *00102 (75.5%), *00103 (8.2%), *00501 (34.0%), *00503 (0.7%), *00504 (0.7%), *00602 (14.4%), *00801 (11.4%), *011 (22.2%), *032 (0.3%), *033 (0.3%) and *034 (0.3%). The ratio of 10A type alleles including 2DL4*00102, *00103, *00501, *00503, *00504, *00602, *032, *033, *034 and 9A type alleles including 2DL4*00801, *011 were 97.0% and 33.0%, respectively, with a ratio of 2.9:1.</p><p><b>CONCLUSION</b>The allelic diversity of the KIR2DL4 gene in southern Han Chinese has been elucidated, which may provide valuable data for research on transplantation, reproductive immunity, KIR-associated disease and evolution.</p>

Targeted resequencing of candidate genes reveals novel variants associated with severe Behcet's uveitis

Behcet's disease (BD) is a chronic systemic inflammatory disorder characterized by four major manifestations: recurrent uveitis, oral and genital ulcers and skin lesions. To identify some pathogenic variants associated with severe Behcet's uveitis, we used targeted and massively parallel sequencing methods to explore the genetic diversity of target regions. A solution-based target enrichment kit was designed to capture whole-exonic regions of 132 candidate genes. Using a multiplexing strategy, 32 samples from patients with a severe type of Behcet's uveitis were sequenced with a Genome Analyzer IIx. We compared the frequency of each variant with that of 59 normal Korean controls, and selected five rare and eight common single-nucleotide variants as the candidates for a replication study. The selected variants were genotyped in 61 cases and 320 controls and, as a result, two rare and seven common variants showed significant associations with severe Behcet's uveitis (P<0.05). Some of these, including rs199955684 in KIR3DL3, rs1801133 in MTHFR, rs1051790 in MICA and rs1051456 in KIR2DL4, were predicted to be damaging by either the PolyPhen-2 or SIFT prediction program. Variants on FCGR3A (rs396991) and ICAM1 (rs5498) have been previously reported as susceptibility loci of this disease, and those on IFNAR1, MTFHR and MICA also replicated the previous reports at the gene level. The KIR3DL3 and KIR2DL4 genes are novel susceptibility genes that have not been reported in association with BD. In conclusion, this study showed that target enrichment and next-generation sequencing technologies can provide valuable information on the genetic predisposition for Behcet's uveitis.

Killer immunoglobulin-like receptor gene genotype and expression pattern in healthy people / 中国实验血液学杂志

The aim of study was to clarify the repertoire of killer immunoglobulin-like receptor (KIR) at the level of DNA and RNA in healthy persons and to compare KIR on genotypes and expression patterns. KIR genotypes including KIR2DL1, 2DL2, 2DL3, 2DL4, 2DL5, 2DS1, 2DS2, 2DS3, 2DS4, 2DS5, 3DL1, 3DL2, 3DL3, 3DS1, 2DP1 and 3DP1 were analyzed by PCR. The phenotypes including KIR2DL1, KIR2DL2, KIR2DL3, KIR3DL1, KIR2DS1, KIR2DS3, KIR2DS2/4 gene were determined by RT-PCR. The results showed that the genes of KIR2DL1, KIR2DL3, KIR2DL4, KIR3DL2, KIR3DL3 and KIR3DP1 could be detected in all healthy persons, NK-92MI cells and Molt4 cells, but all corresponding receptors were not expressed by Molt4 T cells. Only partial transcripts of KIR2DL1, KIR2DL3 and KIR2DS2/4 were detectable in NK-92MI cells. If genotypes of KIR2DL1, 2DL2, 2DL3, 2DS1, 2DS2, 2DS3 and 2DS4 were detected in healthy persons, almost all transcripts of corresponding receptors were expressed in peripheral blood NK cells. The expression levels of KIR were different. In conclusion, the repertoires of KIR are individually specific. The expression pattern of KIR is also specific, the expression levels of different KIRs are different in one individual, and the expression levels of the same KIR are also different in different individuals.

Polymorphism of killer cell immunoglobulin-like receptor gene and its correlation with leukemia / 中国实验血液学杂志

The study was purposed to investigate the polymorphism of killer cell immunoglobulin-like receptor (KIR) gene of the patients with leukemia and to explore the correlation between the KIR gene and susceptibility of leukemia. The KIR genotype of 50 patients with leukemia and 60 healthy controls in northern. Hans were analyzed by PCR-SSP. The results indicated that the present known 18 KIR genes were detected and identified. The frequencies of KIR 3DL3, 3DL2 and 2DL4 were 100% in all subjects, with the most frequent genotype KIR 3DP1 (0.86) followed by 2DP1, 2DL3, 3DL1, 2DL1, 3DS1, 2DL5, 2DS4, 2DS2, 1D, 2DS5, 2DL2, 2DS1, 2DS3 and 3DP1v in leukemia successively. Compared with the control, the KIR 3DL1 (0.60) and 2DL1 (0.57) were significantly lower in the leukemia patient group than that in the control group (1.00) (P < 0.01). It is concluded that the polymorphism of KIR gene is associated with susceptibility of leukemia in Hans. There may be a negative correlation between pathogenesis of leukemia and KIR 3DL1, KIR 3DS1, KIR 2DL1, KIR 2DL5 genes.

Killer Ig-like receptor gene content diversity and haplotype analysis in Chinese Han population in Shanghai / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To detect the diversity of killer Ig-like receptor(KIR) gene content and the combination of haplotypes in Chinese Han population in Shanghai area.</p><p><b>METHODS</b>DNA samples from 87 randomly unrelated healthy individuals in Shanghai Han population were genotyped with SSP/PCR method.</p><p><b>RESULTS</b>(1) Frequencies of KIR genes: All of 18 known KIRs genes, such as 2DL1-5, 2DS1-5, 3DL1-3, 3DS1, KIR1D and the pseudogenes X, Xv and Z(KIR2DP1) were observed in Shanghai Hans. All individuals contain 3DL3, 2DL4, 3DL2 and 3DL1; the most common genes were 2DL3, Z, 2DL1 and X; the following were 2DS4, 1D, 2DL5, 2DS1, 3DS1 and 2DS5; the next were 2DS2, 2DL2, 2DS3 and Xv. (2) Frequencies of KIR gene haplotypes; there were 13 haplotypes detected in 87 Han individuals, among them, the most frequent one was type 2 (haplotypeA-2DS4). (3) Frequencies of KIR genotypes: 18 kinds of the combinations of the haplotypes were observed; the most frequent ones were AJ(2,2), AF (1,2). Also, In this study were identified five new genotypes FZ1 2 9 , FZ2 1 16 , FZ3 6 17 , FZ4 4 13 and FZ5 2 6 ,which had not been observed in Caucasians so far.</p><p><b>CONCLUSION</b>These findings suggest that there are distinctive frequencies of KIR gene content, haplotype as well as genotype in Chinese Han population in Shanghai area.</p>