RESUMEN
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.