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ABSTRACT: To establish a stable and large-scale bi-directional sequencing platform for genotyping MICA gene exons 2 to 4, and to analyze single nucleotide polymorphisms(SNP) of the region.
Primers for particular alleles of MICA gene exons 2 to 5 were designed. Optimal conditions for PCR amplification and sequencing reaction were explored. A commercialized one-way sequencing kit for MICA allele was used as a parallel control. Four samples carrying a MICA *010 allele were subjected to cloning and haplotype sequencing.
Results of MICA allele typing of 100 samples for a parallel control group were confirmed by the establish method. Twenty-two SNP in MICA gene exons 2 to 4 were detected in Chinese population. Two novel allelic sequences were accepted by GenBank and IMGT/HLA database and officially named as MICA*065 and MICA*066 by the WHO Nomenclature Committee. A novel SNP in MICA gene intron 3 was discovered, with allelic sequence submitted to GenBank and IMGT/HLA database.
The bi-directional sequencing genotyping platform may be applied for large-scale study of MICA allelic polymorphisms, tissue typing, organ transplantation and disease research.
Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics 10/2012; 29(5):542-6.
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ABSTRACT: To develop a reliable assay for simultaneous sequence-based typing (SBT) of HLA-DPA1 and HLA-DPB1, and to apply it for the study of allelic polymorphisms in southern Chinese Han population.
Based on full-length HLA-DPA1 and HLA-DPB1 allelic sequences, locus-specific PCR primers were designed and applied to amplify the target sequence encompassing the entire exon 2 of HLA-DPA1 and HLA-DPB1. PCR products were purified with magnetic beads, and run through an ABI 3730 DNA sequencer. Genotypes were assigned with an Assign 3.5 SBT software.
The target sequences of HLA-DPA1 and HLA-DPB1 were both amplified with the PCR procedure. Little background and noise was observed in the derived sequences. Among 176 non-related healthy individuals, 4 HLA-DPA1 alleles with the frequencies of DPA1*02:02 (0.589) > DPA1*01:03 (0.284) > DPA1*02:01 (0.096) > DPA1*04:01 (0.031) were identified. In addition, 14 HLA-DPB1 alleles, including 4 common alleles (with a frequency of more than 5%, namely DPB1*05:01, DPB1*02:01, DPB1*04:01 and DPB1*02:02), 7 alleles with a frequency ranging from 1%-5% and 3 alleles with a frequency of less than 1% were identified. The results of HLA-DPB1 genotyping were all in accordance with the typing results derived from an Atria AlleleSEQR HLA-DPB1 kit.
A reliable technique has been established for simultaneous genotyping of HLA-DPA1 and HLA-DPB1, which may have a broad application in population and disease association studies.
Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics 06/2012; 29(3):323-7.
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ABSTRACT: The HLA-C*07:01:01G allele group consists of three nonsynonymous alleles, C*07:01:01, C*07:06 and C*07:18, plus C*07:01:02, which is synonymous to C*07:01:01. All of these alleles have identical exons 2, 3 and 4, but differ in exons 5 or 6. Therefore routine sequence-based typing (SBT) of exons 2 and 3 is unable to resolve these subtypes, resulting in ambiguous typing results in population and disease cohort studies. In the present study, we fully characterized C*07:01:01G subtypes in European and African Americans and examined their relative frequency distributions. In European Americans C*07:01:01G is predominantly represented by C*07:01:01 (94.4%), whereas C*07:01:02 (1.1%) and C*07:18 (4.5%) were detected relatively infrequently. In African Americans C*07:18 (42.4%) showed a high frequency similar to that of C*07:01:01 (44.7%) whereas C*07:06 was detected at a low frequency (4.7%). C*07:06 was found exclusively on B*44:03 carrying haplotypes in both ethnic groups, but C*07:18 showed multiple linkage relationships with HLA-B. These results demonstrate that C*07:01:01G as defined by routine SBT is a heterogeneous group of alleles, especially among individuals of African origin. If C*07:01:01G subtypes prove to bear divergent functional significance, it would be necessary to include these subtypes in routine HLA-C typing for clinical transplantation and disease association studies.
Human immunology 04/2012; 73(7):715-9. · 2.55 Impact Factor
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ABSTRACT: Differential expression of human leukocyte antigen C (HLA-C) allotypes is mediated by the binding of a microRNA, miR-148a, to the 3' untranslated region of some, but not all, HLA-C alleles. The binding results in lower levels of HLA-C expression, which is associated with higher levels of HIV-1 viral load among infected individuals. The alternative set of HLA-C alleles has several substitutions in the miR-148a binding site that prevent binding and HLA-C downregulation; these high-expression alleles associate with control of HIV-1 viral load. We show that the common ancestor of all extant HLA-C alleles was suppressed by miR-148a. Substitutions that prevent miR-148a binding arose by a sequence exchange event between an HLA-C allele and an HLA-B (MIM 142830) allele of a B(∗)07-like lineage. The event occurred 3-5 million years ago, resulting in an HLA-C variant that escape from miR-148a downregulation. We present evidence suggesting that selection played a role in the successful spread of the HLA-C escape alleles, giving rise to 7 of the 14 extant HLA-C lineages. Notably, critical peptide and KIR binding residues of the escape variants have selectively converged to resemble the sequence of their inhibited counterparts, such that the inhibited and escape groupings differ primarily by their levels of expression.
The American Journal of Human Genetics 09/2011; 89(3):424-31. · 10.60 Impact Factor
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ABSTRACT: To analyze the human leukocyte antigens(HLA)-A, -B, -Cw, -DRB1 and DQB1 nucleotide sequences between patients waiting for allogenic hematopoietic stem-cell transplantation (HSCT) and donors in Chinese population, and to establish strategy for maximizing optimal donor selection.
HLA high-resolution typing in a total of 537 recipient-donor pairs was determined by sequence based typing (SBT) method. The nucleotide BLAST tool was used to compare the nucleotide sequences among recipient-donor pairs.
Only 16.20% (88/537) of recipient-donor pairs were found to fully match for nucleotide sequences of all HLA-A,-B,-Cw, -DRB1 and -DQB1 loci. Mismatch rate in single locus were 8.38% in HLA-A, 0.74% in HLA-B, 12.29% in HLA-C, 2.42% in HLA-DRB1, and 2.79% in HLA-DQB1, respectively. Mismatch rate in two or multiple HLA loci was 42.65%. Nonpermissive allele mismatch combinations (A 02:01-A 02:06, A 02:06-A 02:07, Cw 03:04-Cw 15:02, Cw 03:03-Cw 04:01, Cw 03:04-Cw 14:02, Cw 03:03-Cw 08:01, DRB1 04:03:01-DRB1 04:05) were detected in single mismatch HLA locus of recipient-donor pairs, mismatches of B 07:05:01-B 07:06, Cw 07:01:01-Cw 07:06 combinations outside of epitope positions were detected in two recipient-donor pairs.
Our data suggested that attention should be paid in comparing nucleotide sequences between recipient and donor, and in distinguishing nucleotide sequence mismatches within and outside of the epitope positions. These results could serve as guidelines for donor selection.
Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics 08/2011; 28(4):450-4.
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ABSTRACT: To identify a novel human leukocyte antigen (HLA) allele A*02:251 and analyze the sequences in Chinese population.
Routine HLA-A, -B, -DRB1 high resolution genotyping for healthy Chinese donors and patients was performed with polymerase chain reaction-sequence based typing. An unknown HLA-A allele was initially detected by HLA typing in the healthy donor. Genomic DNA of the HLA-A locus in the proband was amplified, the amplified product was cloned by PMD18-T to split the two alleles, and selected clones were sequenced.
The sequencing results showed that a normal A*02:06:01 and a novel A*02:251 variant allele were identified. The sequence of the novel allele has been submitted to GenBank (HM245348). Nucleotide sequence alignments with HLA-A allele from the IMGT/HLA Sequence Database showed that the novel A*02 variant allele differed from the closest allele A*02:01:01:01 by nt 383 G to C (codon 128 GAG to GAC) in exon 3, which resulted in one amino acid substitution of Glu to Asp. The HLA-A, B, C and DQB1 alleles of the healthy donor did not match with that of the patient.
This novel allele is officially designated as HLA-A*02:251 by World Health Organization(WHO) Nomenclature Committee (Submission ID HWS10010755). The sequence of HLA-A locus in exon 3 is confirmed to be polymorphic in Chinese population.
Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics 06/2011; 28(3):300-3.
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ABSTRACT: Human chimerism is the presence of ≥ 2 cell populations in one person that contain genetic material from more than one zygote. Chimerism may be either acquired by transfusion or transplantation of donor cells, or congenital arising from embryo fusion or dizygotic twin-twin transfusion. We encountered a 4-year-old boy with developmental hip dysplasia whose preoperative (serologic) blood group was AB, but whose red cell agglutination was atypical ("mixed field") and caused us to study the patient's parents' ABO blood groups. Parental blood groups (AB and O) suggested possible nonparentage. An alternative explanation of the findings was that the child was chimeric or mosaic. Molecular cloning and genotyping of his ABO locus in leukocytes revealed two heterozygous genotypes: A102/O01 and B101/O01. Other loci, each of which possessed three distinct alleles, unambiguously showed transmission of two alleles from either the child's mother (e.g., HLA-A) or two alleles from the child's father (e.g., D8S1179). Findings indicate that the child is a tetragametic chimera.
Journal of Forensic Sciences 05/2011; 56(5):1346-8. · 1.23 Impact Factor
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ABSTRACT: To evaluate the accuracy of SBT protocols for HLA-C and to better understand the HLA-C polymorphism in Chinese, 1795 unrelated CMDP donors were typed at exons 2, 3, and 4 of the HLA-C gene using the Atria commercial kit. Of the study subjects, 1768 showed conclusive typing results, whereas the other 27 showed inconclusive results. Subsequent full-length cloning and haplotype sequencing showed that 11 of the 27 inconclusive results could be explained by the presence of nine novel alleles identified: Cw*0130, 0624, 070206, 075602, 0766, 0767, 0820, 0821, and 0827. These novel alleles were generated by a total of 10 coding-region substitutions, eight of them being located in the antigen-binding groove. Cw*0766 and Cw*075602 were detected three and two times, respectively, in the 1795 donors. The other 16 inconclusive samples were retested by SBT using our in-house PCR primers; all of them were found to carry Cw*0706, which dropped out in exons 2 and 3 in the initial PCR using the commercial primers amplifying from 5' UTR to intron 3. Our results showed the importance of the full-length genomic sequence and intronic SNPs for the development of more accurate SBT. The allele distribution and novel alleles detected in this study also provide further insights into the HLA-C polymorphism in the Chinese Han population.
Human immunology 03/2010; 71(6):577-81. · 2.55 Impact Factor
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ABSTRACT: To analyze the possible reason for HLA-C allele dropout in routine sequence-based typing (SBT) and improve the accuracy of HLA-C SBT test.
A total of 620 randomly selected samples from healthy voluntary blood donors in Shenzhen were typed at HLA-C locus by sequence-based typing using the AlleleSEQR HLA-C plus sequence-based typing kit. Samples with no full match result were subjected to cloning and haplotype sequencing of the full-length HLA-C gene. If no novel mutations were found, samples were then retyped, using our self-designed PCR primer pair and PCR conditions replacing the AlleleSEQR HLA-C PCR reagents in the PCR set-up procedure so as to analyze the potential reasons for causing abnormal SBT result.
In the 620 samples typed at HLA-C locus using the AlleleSEQR HLA-C SBT commercial kit, 5 samples with no full match result were identified. The closest genotype showed one nucleotide mismatch with many different allele groups at different nucleotide position. Based on the PCR-SBT nucleotide sequence, heterozygous nucleotides were determined only in exon 4, whereas the nucleotides in exon 2 and 3 were all homozygotes. The results showed that HLA-Cw*0706 allele dropout existed in all the 5 samples with abnormal SBT results initially identified by AlleleSEQR HLA-C SBT kit, no novel mutation was found.
The results indicate that the PCR primer pair incompatible with DNA template may result in allele dropout in HLA-C SBT test. Based on the characterization of HLA-C full-length, it is essential to develop HLA-C SBT kit suitable for Chinese population in the future.
Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics 10/2009; 26(5):562-6.
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ABSTRACT: We report two novel HLA-C alleles, Cw*0766, and Cw*0767 identified in a Chinese voluntary stem cell donor. This sample was initially found by direct PCR-SBT with an inconclusive result. To clarify this unusual SBT result, the PCR product of HLA-C gene covering from exon 1-4 was subjected to cloning and haplotype sequencing and family study of HLA inheritance consisting of six members were confirmed. Novel Cw*0766 allele differs from the closest allele Cw*07020101 by single nucleotide change at genomic DNA nt 1651 C>A (codon 206 CTG>ATG) in exon 4, which results in an amino acid change Leu206Met. Another novel allele Cw*0767 differs from the closest allele Cw*07020103 by single nucleotide change at genomic DNA nt 930 A>T (codon 161 GAG>GTG) in exon 3, which results in an amino acid change Glu161Val. Family study demonstrated that the novel Cw*0766 allele segregating on an A*2402 B*4001 Cw*0766 DRB1*1202 haplotype was inherited from the mother of the propositus, whereas the novel Cw*0767 allele on haplotype A*1101 B*0702 Cw*0767 DRB1*0101 was inherited from the father.
Human immunology 10/2009; 71(1):93-5. · 2.55 Impact Factor
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ABSTRACT: To establish a reliable assay for cloning and sequencing the full-length HLA-Cw gene.
In this study, a fragment of 4.5 kb full-length HLA-Cw gene was amplified using the self-designed PCR primer pair by long template PCR, purified PCR products was cloned into the pGEM-Teasy plasmid vector and the plasmid DNA isolated from positive clones was subjected to haplotype sequencing by both directions. A total of 12 samples having been previously-genotyped by PCR sequence-based-typing (PCR-SBT) were amplified by using the TaKaRa LA Taq and Stratagene Pfu polymerase, respectively. PCR products of full length HLA-Cw gene were subjected to cloning and sequencing and the obtained haplotype sequence were compared with the PCR-SBT results.
The specific target fragment of HLA-Cw gene could be amplified and the full-length HLA-Cw allele sequence covering from nucleotide position -962 in 5'untranslated region (5'-UTR) to nucleotide position 3576 in downstream area of 3'-UTR region could be obtained using our method. The results of cloning and sequencing analysis indicated that the Stratagene Pfu polymerase had better fidelity than the TaKaRa LA Taq polymerase in this experiment. By comparing the sequences of Cw*07020101 with Cw*010201, 11 SNPs as well as 2 insertions/deletions in nt-962--284 of 5'-UTR, and 11 SNPs as well as 1 insertion/deletion in nt3067-3576 downstream of 3'-UTR were identified.
Our results indicate that the technique for cloning and sequencing full-length HLA-Cw gene has been established, it has a broad application in full-length HLA-Cw gene polymorphism study and the regulation and expression of HLA-Cw gene.
Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics 07/2009; 26(3):258-62.
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ABSTRACT: To identify a novel human leukocyte antigen (HLA) allele by cloning and sequence-based typing in Chinese population, and analyzing the sequence of the introns 1 and 2.
The routine HLA-A, -B, -DRB1 low resolution genotyping for stem cell donor from Guangdong province was performed with polymerase chain reaction-sequence specific oligonucleotide probes (PCR-SSOP). An unknown HLA-DRB1 allele was initially detected by HLA typing. Genomic DNA of the proband was amplified by using HLA-DRB1 locus group-specific primer, the amplified product was cloned, sequenced, and compared to the closest DRB1*120201 allele and the closest intron sequence of the DRB1*030101 allele.
The sequencing results showed that a normal DRB1*080302 and a novel DRB1*1218 variant allele were identified. The sequence of the novel allele has been submitted to GenBank (FJ481086). The novel allele had 1 nucleotide substitution of the closest matching allele HLA-DRB1*120201 at nt262(G-->C) in exon 2,resulting in an amino acid change from Glu(GAG)-->Gln (CAG) at codon 59.The intron 2 sequence is identical between the novel HLA-DRB1*1218 and DRB1*030101, but there are 12 nucleotides substitution in intron 1.
A novel HLA allele was confirmed by cloning and sequence-based typing in Chinese. It was officially designated as HLA-DRB1*1218 by WHO Nomenclature Committee.
Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics 06/2009; 26(3):272-6.
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ABSTRACT: To analyze the polymorphism and haplotypes of HLA-A, B, Cw, DRB1 and DQB1 loci in Chinese Han population.
A total of 186 unrelated healthy individuals from southern China were analyzed by sequence-based typing. Two-, three-, and five-locus haplotypes were estimated using the Expectation Maximization Algorithm. RESULTST: Twenty-eight alleles for the HLA-A locus, 49 HLA-B alleles, 24 HLA-C alleles, 29 HLA-DRB1 alleles and 20 HLA-DQB1 alleles were detected. The A*0207-B*4601(10.81%), A*3303-B*5801(6.14%), B*4601-DRB1*0901(6.22%), B*4001*-DRB1*0901(3.78%), DRB1*090-DQB1*0303 (12.16%) and DRB1*1202-DQB1*0301(8.38%), A*0207-B*4601-Cw*0102 (10.75%), A*3303-B*5801-Cw*0302 (5.14%), A*0207-B*4601-DR*0901(5.07%), A*3303-B*5801-DRB1*0301(2.96%), A*0207-B*4601-Cw*0102-DRB1*0901-DQB1*0303(4.87%) and A*1101-B*1301-Cw*0304-DRB1*1501-DQB1*0601(2.43%) were the most common haplotypes in the southern Chinese Han population.
The results have shown the characteristics of the five HLA loci haplotype distribution and provided more information in anthropology, disease association studies and transplantation.
Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics 05/2009; 26(2):228-32.
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ABSTRACT: To analyze the difference between the frequencies of HLA-A-B, B-DRB1 and A-B-DRB1 haplotype, as well as their linkage disequilibrium pattern in patients with acute lymphoblastic leukemia(ALL) and healthy controls from Northern Chinese Han.
The frequencies of HLA-A-B, B-DRB1, A-B-DR haplotypes and linkage disequilibrium were estimated by Expectation Maximization method based on the genotypes of 643 patients with ALL and 2 0359 unrelated healthy donors, and the statistical significance between the two groups were estimated by chi-square test. Linkage disequilibrium was analyzed with population genetic methods.
The most common HLA-A-B, B-DRB1, and A-B-DR haplotypes were A30-B13, A2-B46, A33-B58, B13-DR7, B46-DR9, B52-DR15, B58-DR17, A30-B13-DR7, A33-B58-DR17 and A1-B37-DR10 in both groups. The frequencies of A30-B13, A2-B46, A33-B44, B13-DR7, A30-B13-DR7 and A2-B46-DR9 haplotypes and linkage disequilibrium value were significantly decreased (P<0.05) in the patient group than that in the control group. On the other hand, the frequencies of A2-B52, A31-B61, A24- B8, B60-DR9, B27-DR4, B52-DR14, B44-DR17, B27-DR12 and A11-B27-DR12 haplotypes and linkage disequilibrium value were significantly increased (P<0.05) in the patient group than that in the control group.
There are some common and positive linkage disequilibrium haplotypes in both the ALL patients and the healthy donors in Northern Chinese Han. Interestingly, some haplotypes and their linkage disequilibrium patterns had significantly different distributions between the two groups. The study provided basic data for the relationship of ALL and HLA haplotype and for finding the HLA-A, B, DR matching donors.
Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics 02/2009; 26(1):82-6.
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ABSTRACT: To study the gene polymorphism of the Auberger antigens in Lutheran blood group system in Chinese population and establish a stable, accurate molecular method detecting Auberger antigens.
Peripheral blood samples from 162 randomly collected and unrelated volunteer blood donors were directly sequenced for the exon 12 at the gene locus of Auberger antigens. PCR products with novel nucleotide were further investigated by restriction fragment length polymorphism (RFLP) analysis.
Auberger genotypes in the 162 Chinese individuals were obtained: Au(a+ b- )(nt1615A) was found in 119 individuals, Au(a+ b+ ) (nt1615A/G) in 40 individuals and Au(a- b+ ) (nt1615G) in 3 individuals. The allele frequencies of the Au(a) and Au(b) were 0.8580 and 0.1420, respectively. An individual with homozygous Au(a) genotype had a nucleotide mutation (1595 G to T). The mutation was confirmed by digesting the DNA with Hha I.
The distribution of gene polymorphism of Auberger antigens in a Chinese population was investigated and obtained. And a molecular method determining the Auberger antigen was established. A novel Lutheran allele was deposited in GenBank (accession number EU260043).
Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics 01/2009; 25(6):663-6.
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ABSTRACT: Human Y-Chromosome specific STR (Y-STR) has now become a useful loci in casework. However, noninvasive genotyping of multiple Y-STR loci and its application in prenatal genetic diagnosis haven't been reported. The purpose of this study is to develop a Y-STR multiplex PCR amplification system that is suitable for the amplification of short-sized templates of circulatory male fetal DNA and use the established multiplex in noninvasive prenatal genetic diagnosis and its further applications in forensic casework.
On the basis of the characteristic of circulatory fetal DNA in maternal plasma, we selected 9 Y-STR loci in which the allele size was less than 180 bp in length and developed two multiplexes that allowed fluorescent genotyping of 9 Y-STR loci simultaneously. These Y-STR loci include two trinucleotide repeats (DYS426 and DYS388) and seven tetranucleotide repeats (DYS393, DYS460, H4; DYS391, DYS389 I, DYS456 and DYS458). Sixty-four pairs of plasma DNA samples from pregnant women and genomic DNA samples from their husbands were detected by our method.
As a result, an average of 7.3 Y-STR specific alleles was detected in each of the 30 plasma DNA samples from pregnancies with male fetuses. However, none of these 9 Y-STR specific alleles was detected in 34 plasma samples from pregnant women carrying female babies. The chances of detecting Y-STR alleles ranged from 66.7 to 93.3%. Fifty-eight haplotypes were detected in 64 unrelated Chinese male individuals; haplotype diversity was 0.9966. This highly polymorphic Y-STR multiplex has greatly improved the chances of detecting the Y-STR allele.
This assay provides a sensitive, accurate and efficient method for noninvasive prenatal genetic diagnosis and forensic casework.
Prenatal Diagnosis 05/2006; 26(4):362-8. · 2.11 Impact Factor
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ABSTRACT: To study the molecular genetic background of B subtype in Chinese Han population and identify novel allele at the ABO locus.
Ten samples from randomly selected blood donors of normal B phenotype used as control, and six samples from individuals diagnosed as B subgroup by serological tests were genotyped by sequence specific primer polymerase chain reaction and direct DNA sequencing at the exons 6 and 7 of ABO gene. The exons 6 and 7 and the intervening intron 6 of the B allele from each B subgroup sample were analyzed by cloning and haplotype sequencing.
A novel B variant allele was identified in two individuals whose blood samples were diagnosed as belonging to Bx subgroup and Bw subgroup respectively, the novel B allele being different from the allele B101 by single 695T>C missense mutation in exon 7. A family with the individual possessed Bx subgroup was studied. Among 22 family members tested, seven family members were found to carry the novel B variant allele. No novel point mutation at the exons 6 and 7 of ABO gene were detected in the ten control samples and the other four samples with B subgroup.
The present authors define this allele as a novel B variant allele. The mutation of this novel allele, in which the nucleotide alters from T to C at position of 695 in exon 7 and hence results in an amino acid change from Leu to Pro, is expected to diminish the enzyme's activity. It indicates that the alteration of amino acid at the position of 232 is critical to the activity of glycosyltransferases.
Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics 04/2005; 22(2):129-33.
