Identification of an HLA-A11 serological variant and its characterization by sequencing based typing

We have identified an HLA‐A11 variant allele, A*1105, segregating in a Caucasoid family. The variant antigen expressed by this allele failed to cross‐react with most Caucasoid anti‐HLA‐A11 antisera tested. Sequencing based typing has been used to characterize this new allele and this showed that it has a novel mutation at a polymorphic position (502) in exon 3. In comparison with A*1101, the mutation (A→G) results in an amino acid change from positively‐charged lysine to negative glutamate and this may explain the altered HLA‐A11 serological profile exhibited by this antigen. The new allele was found in a patient with acute lymphoid leukaemia (ALL), her father and two siblings Note.