Analysis of frequency and molecular genetics of Jk (a-b-) phenotype among blood donors from Jining area

Abstract

To screen for Jk(a-b-) phenotype among blood donors from Jining area and explore its molecular basis to enrich the rare blood group bank for the region. The population who donated blood gratuitously at Jining Blood Center from July 2019 to January 2021 were selected as the study subjects. The Jk(a-b-) phenotype was screened with the 2 mol/L urea lysis method, and the result was confirmed by using classical serological methods. Exons 3 to 10 of the SLC14A1 gene and its flanking regions were subjected to Sanger sequencing. Among 95 500 donors, urea hemolysis test has identified three without hemolysis, which was verified by serological method as the Jk(a-b-) phenotype and demonstrated no anti-Jk3 antibody. The frequency of the Jk(a-b-) phenotype in Jining area is therefore 0.0031%. Gene sequencing and haplotype analysis showed that the genotypes of the three samples were JK*02N.01/JK*02N.01, JK*02N.01/JK-02-230A and JK*02N.20/JK-02-230A, respectively. The splicing variant of c.342-1G>A in intron 4, missense variants of c.230G>A in exon 4, and c.647_ 648delAC in exon 6 probably underlay the Jk(a-b-) phenotype in the local population, which is different from other regions in China. The c.230G>A variant was unreported previously.