Distribution of MICA diversity in the Chinese Han population by polymerase chain reaction sequence‐based typing for exons 2–6

Abstract Major histocompatibility complex class I chain‐related gene A ( MICA ) is located 46 kb centromeric to HLA‐B locus and encodes a stress‐inducible protein. MICA allelic variation is thought to be associated with disease susceptibility and immune response to transplants. In this study, polymerase chain reaction sequence‐based typing (PCR‐SBT) method for MICA alleles has been established. Genomic DNAs from 100 healthy Chinese Han individuals were typed for MICA alleles by this method. The microsatellite polymorphism in the exon 5 of MICA gene, MICA * Del allele, and human leukocyte antigen‐B alleles was also detected by the polymerase chain reaction–GeneScan, polymerase chain reaction sequence‐specific primer, and PCR‐SBT methods, respectively. Fourteen MICA alleles were found in the population, with MICA * 00801/04 having the highest frequency of 27.0%. MICA * A4 , * A5 , * A5.1 , * A6 , and * A9 microsatellites were identified. Two samples with HLA‐B * 4801 were MICA * Del positive, with the frequency of 1.0%. The data showed that the new PCR‐SBT method for MICA alleles was reliable and Chinese Han population was distinct in distribution of MICA alleles.