Complete sequence analysis of the A*1103 allele

Here we report the full-length sequence of a novel A*11 variant. The variant was identified by ARMS-PCR and serology; the sequence was confirmed by cloning and subsequent sequencing. This variant, A*1103, found in a family of oriental origin, resembles the A*1101 sequence in exon 2 but differs in exon 3 with regard to codons 151 and 152. The polymorphism's result in two amino acid substitutions (one conserved (His->Arg) one introducing a negative charge (Ala->Glu)) located in the α2 helical region. The arginine at amino acid position 151 is rare amongst A-locus alleles and is besides A*1103 only observed in A*29 variants, the glutamine at amino acid position 152 is shared with A*0301, A*25, *26, *34 variants and the A*02 subtypes A*0203, *0213 and *0226. In fact, the amino acid motif comprising codons 151 and 152 is unique to A*1103 among A-locus alleles, but is common to C-locus alleles.