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【Objective】 To explore the molecular hereditary and frequency of Jk(a-b-) in blood donors in Yichang. 【Methods】 A total of 49 999 samples from Yichang Red Cross Central Blood Station were screened for Jk(a-b-) by urea hemolysis test(2 mol /L). The phenotypes of JK (a-b -) probands and their families were confirmed by monoclonal anti-Jka and anti-Jkb, and the whole exon of SLC14A1 gene was sequenced. 【Results】 The frequency of Jk(a-b-) in Yichang blood donors was 0.004% (2/49 999), and the exon sequencing of SLC14A1 gene confirmed that both two probands were JK*02N.01 caused by c. 342-1G>A homozygous mutation.Besides, JK*01W.01 allele was observed in the pedigree analysis, and weak expression of Jka was found in 4 out of 11 family members. 【Conclusion】 The frequency of JK (a-b -) in Yichang blood donors is similar to those in Shanghai 0.004%(2/48 400), and both caused by JK * 02N.01 allele with high frequency in Southeast Asia. The epidemiological survey of JK * 01w.01 allele frequency should be further performed.
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Objective To investigate the frequency of Jk(a-b-) phenotype of Kidd blood type system in blood donors of Fujian province and its genetic characteristics.Methods The Jk (a-b-) phenotype in the blood samples obtained from 180 626 donors were screened by using urea lysis assay and the suspected Jk(a-b-) pbenotype individuals were confirmed using conventional serological method.The genomic DNA covering the sequence from exon 1 to exon 11 of JK gene and respective flanking area(50-150 bp),as well as the promoter were amplified by polymerase chain reaction,and the products of PCR were directly sequenced.The genotypes of 7 SNPs of JK gene in the blood samples from 200 blood donors of Fujian province were detected by SNaPshot assay.Results Of 180 626 blood donors,15 cases with Jk(a-b-) phenotype were identified.The genomic analysis for the 15 cases revealed the four recessive JK-null alleles,i.e.,JK*B(IVS5-1G＞A),JK*B(896G＞A),JK*A(130G＞A,220A ＞G) and JK* B(130G ＞A,956C ＞ T) were observed with frequency of 66.67％,23.33％,6.67％ and 3.33％,respectively.SNaPshot results showed the frequency of JK * B (IVS5-1 G ＞ A) was 0.75 ％ and G130A was the common polymorphism.No A220G,C222T,C956T and G896A mutation was found in the 200 blood donors.Conclusion The frequency of Jk (a-b-) blood type in the donors of Fujian population was estimated about 0.008％.JK * B(IVS5-1G ＞ A) and JK * B(896G ＞ A) alleles may be the predominate circulating genes in Fujian population with Jk (a-b-) phenotype.Direct DNA sequencing revealed a novel allele leading to JK-null,SLC14A1 130A,220G.
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Objective To study the distribution of Jk(a-b-) phenotype in the blood donors of Panyu district. Methods Negative samples were screened by U type 96 well microplate technology, and then confirmed by routine serologic testing. The Jk(a-b-) phenotypes were genotyped and the genomic DNA coding region covering 4-11 exons and their flanking region were expanded and sequenced. Results Ten Jk(a-b-) phenotypes were found out of 50034 donors from June 2004 to August 2006, with the frequency of 0.02%. Three kinds of mutation sequences were detected: 1) AG to AA in the 3' splice site of intron 5; A to G at 588 site, and AA196CCA to CCG in exon 7. The genotype presumed to be JKb(△6)/ JKb(△6).2) C to A at 222 site of exon 5, and AA74AAC to AAA ; C to G at 536 site of exon 7, and AA179CCT to CGT; A to G at 588 site of exon 7,and AA196CCA to CCG. The genotype is presumed to be JKb(222A)/JKb(536G).3) AG to AA in the 3' splice site of intron 5;A to G at 499 site of exon 7,and AA167ATG to GTG; A to G at 588 side of exon 7,and AA196CCA to CCG. The genotype is presumed to be JKb(△6)/JKb(499G). Conclusions Two novel mutations, A to G at 499 side of exon 7 and C to G at 536 site of exon 7, are first discovered.
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Objective To investigate the molecular basis for Jk(a b ) phenotype.Methods Routine serologic testing for phenotype.Genomic DNA covering 4～11 exons and partial introns of JK gene was amplified by ploymerase chain reaction.The PCR products were excised and purified from agarose gels with a kit,then fragments were directly sequenced.Results G mutated to A in the 3'acceptor splice site of intron 5;A to G at 78 site from the 3'end of intron 3;C to T at 84 site from the 5'end of intron 8; A to G at 588 site of exons ( exon 7); G to A at 838 site of exons (exon 9).The splice site mutation (G→A) of intron 5 may cause the skipping of exon 6.Conclusion G to A mutation in the 3'acceptor splice site of intron 5 maybe one of the molecular basis for Jk(a-b-) phenotype