ABSTRACT
【Objective】 To investigate the distribution and molecular basis of A2 subtype among blood donors in Guangzhou. 【Methods】 Whole blood samples of 793 group A blood donors in Guangzhou Blood Center were randomly collected. A2 subtype was screened by anti-A1 lectin in 96-well plate, and ABO typing was confirmed by the tube test. Then, the genomic DNA of A2 subtype blood donors was extracted, and the exons 6-7 of ABO gene were sequenced to determine the genotype of A2 subtype. 【Results】 Among 793 group A blood donors, there were 13 cases of A2 subtype, and the frequency in group A was 1.64%(13/793). The sequencing results of exons 6-7 of ABO gene showed that 10 of the 13 A2 subtypes carried A2 alleles, which were ABO*A2.05/ ABO*O.01.01 (n=5), ABO*A2.05/ ABO*O.01.02(n=2), ABO*A2.01/ABO*O.01.01(n=1) and ABO*A2.01/ ABO*O.01.02(n=2), respectively. The other 3 cases only carried ABO*A1.02 alleles. 【Conclusion】 The main genotype of A2 subtype in Guangzhou is ABO*A2.05, followed by ABO*A2.01.
