6.3
#219
HLA-B*4405: CONFIRMATION OF EXON 2 DNA SEQUENCE AND ASSOCIATION WITH CW2.
Maureen Carr BA, MBA , Dawn M. Thomas, BS and Edward J. Ball, Ph.D. . Cleveland OH, USA, the Cleveland Clinic Foundation, 44195, Allogen Laboratories .

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HLA-B*4405 was described by Yao et al and Petersdorf et al in 1994 as a B*44 variant allele that differed from B*4402 by a single nucleotide at position 418 (T vs G) in exon 3 (aa 116 Y vs D) . Until April 2003, the WHO reference sequence for B*4405 had only partial data for exon 2, leading us to obtain full exon 2 sequence data for our local examples of presumed B*4405 alleles based on PCR-SSOP typing. Among 265 Caucasian transplant candidates, 57 (21.5%) were B*44, representing 60 genes. Three different alleles (allele groups) were represented: B*4402 = 44/60 (73%), B*4403 = 11/60 (18%), B*4405 = 5/60 (8%). Within the B*4402 group, attributed Cw alleles were: Cw*0501/03 (34/44 =77%), Cw*0704/11 (8/44=18%), Cw*1203 (1/44=2%), Cw*15 (1/44=2%). Within the B*4403 group, attributed Cw* alleles were Cw*1601 (6/11=55%) and Cw*04 (5/11=45%). Within the B*4405 group, attributed Cw alleles were Cw*0202/04 in all cases (5/5=100%). Four of the five cases were also DRB1*0101. Full exon 2 and exon 3 sequencing of each of the five B*4405 cases demonstrated that the entire exon 2 sequence was identical to B*440201. These results are consistent with the recently reported exon 2 sequence for B*4405 (AF251563, AY188943, AJ535113, AY194116). This study confirms the exon 2 and exon 3 nucleotide sequence of B*4405 and the suggestion that this allele is part of an extended haplotype of Cw*0202, B*4505, DRB1*0101.