Bannai M, Tokunaga K, Tanaka H, Lin L, Kashiwase K, Tokunaga K, Juji T
Department of Research, Japanese Red Cross Tokyo Metropolitan Blood Center, Japan.
Tissue Antigens. 1997 Apr;49(4):376-82. doi: 10.1111/j.1399-0039.1997.tb02765.x.
HLA-B22-group alleles in Japanese were identified using PCR-single-strand conformation polymorphism (SSCP) and sequence analyses. We analyzed genomic DNAs obtained from Japanese individuals positive for HLA-B22 group antigens (HLA-B54, B55, B56) including two locally proposed splits (B55.2, and B22N). In the SSCP analysis of both exons 2 and 3, we discriminated five different B22-group alleles. Each allelic pattern corresponded to each serological split antigen. Direct sequencing analysis of exon 2 and exon 3 showed that alleles encoding B54, B55.1 and B56 antigens in Japanese are encoded by B5401, B5502 and B5601, respectively, and those encoding B55.2 and B22N antigens are previously unidentified alleles, B5504 and B5603, respectively. Full-length cDNA sequencing showed that the B5603 sequence is identical to those of B5501, B5502, B5601, and B5602 in exons 1 to 2 except for a synonymous substitution at nucleotide position 165 in exon 2. On the other hand, the sequence of exons 3 to 7 was identical to those of some B15 and B46 alleles, suggesting that B5603 was generated by a recombination event between one of the B55 and B56 alleles and one of the B15 and B46 alleles in intron 2. As for B5504, the entire exon 1 to 7 sequence is identical to that of B*5502 except that the 5'-half of the exon 3 sequence is identical to those of some B7, B27, B40 and B48 alleles, suggesting that an event such as gene conversion, segmental exchange, or double recombination occurred in this region.
采用聚合酶链反应-单链构象多态性（PCR-SSCP）和序列分析方法鉴定了日本人群中的HLA-B22组等位基因。我们分析了从HLA-B22组抗原（HLA-B54、B55、B56）呈阳性的日本个体中获得的基因组DNA，其中包括两个本地提议的分型（B55.2和B22N）。在第2外显子和第3外显子的SSCP分析中，我们区分出了5种不同的B22组等位基因。每种等位基因模式都对应于每种血清学分型抗原。第2外显子和第3外显子的直接测序分析表明，日本人群中编码B54、B55.1和B56抗原的等位基因分别由B5401、B5502和B5601编码，而编码B55.2和B22N抗原的等位基因是先前未鉴定的等位基因，分别为B5504和B5603。全长cDNA测序表明，B5603序列在第1外显子至第2外显子中与B5501、B5502、B5601和B5602的序列相同，只是在第2外显子的核苷酸位置165处有一个同义替换。另一方面，第3外显子至第7外显子的序列与一些B15和B46等位基因的序列相同，这表明B5603是由第2内含子中B55和B56等位基因之一与B15和B46等位基因之一之间的重组事件产生的。至于B5504，第1外显子至第7外显子的整个序列与B*5502的序列相同，只是第3外显子5′端的一半序列与一些B7、B27、B40和B48等位基因的序列相同，这表明该区域发生了基因转换、片段交换或双重组等事件。
