A SILENT MUTATION IN HLA-DPB1(ASTERISK)0101 AND ITS EVOLUTIONARY IMPLICATIONS

A novel HLA-DPB1 allele (DPB1+WA6) has been identified in West Africa, and the occurrence of the recently reported allele DPB14001 (DPB1*BR I-5) in Negroid populations has been confirmed DPB1WA6 differs from D PB10101 by a silent nucleotide exchange at codon position 43 only. It constitutes, thereby, a link to DPB11101, *1501, and *2601 and sugge sts an evolutionary relationship with these alleles. Carrying the same silent mutation, DPB11101, *1501, and *2601 may, by recombinations, have evolved from DPB1WA6. An apparently older evolutionary branch ar ose directly from DPB10101 and comprises the closely related alleles DPB12701 and DPB1*4001 reported only from individuals of African desc ent.