BOTH HLA-B-ASTERISK-1301 AND B-ASTERISK-1302 EXIST IN ASIAN POPULATIONS AND ARE ASSOCIATED WITH DIFFERENT HAPLOTYPES

A B13 split antigen was newly identified with three alloantisera in Japanese, and two B13 split antigens were found in a Thai family. To confirm the variation of B13 and understand the correspondence between the serologic splits and the published B13 alleles, B(*)1301 and B(*)1302, we determined the sequences of genes coding for these B13 splits. The common Japanese B13 allele was found to be B(*)1301, whereas another split antigen was shown to be coded by B(*)1302. Two B13 variants identified in a Thai individual corresponded to B(*)1301 and B(*)1302. Moreover, 57 B13-positive samples from several ethnic groups were examined using the PCR-SSO method. Differing from previous reports, both B(*)1301 and B(*)1302 were found in samples from Asian populations. These two alleles were separately associated with different antigens: HLA-B(*)1301 exhibited a strong association with A2, Cw10, DR12, and DQ7 antigens, whereas HLA-B(*)1302 was strongly associated with A30, Cw6, DR7, and DQ2 antigens. In addition, applying the PCR-SSCP method, B(*)1301 and B(*)1302 could also be simply distinguished from each other.