Sequencing studies of HLA class II molecules have focused almost exclu
sively on exon 2. In this study the complete cDNA sequence of the DRB1
09012 allele is reported for the first time. This sequence was previo
usly only partially published. In the DR9 antigen, two synonymous alle
lic variants (DRB109011 and 09012) were officially recognized, though
it was later found that the first one contained an error and both seq
uences were, thus, identical.