HA-1 gene expression in 65 HLA-A2–positive healthy blood donors, hematopoietic cell lines, and primary leukemic blasts by allele-specific RT-PCR. PCR using HA-1 allele-specific primers was performed as previously described,2 resulting in a 255-bp fragment. Results from representative samples from homozygous (HA-1^H/H) (including CROFT and cell line HH [6574805; kindly provided by Dr E. Goulmy]) and heterozygous (HA-1^H/R) HA-1–positive cell lines (OPM2 and KG1) or primary leukemic blasts (1, 2, and 3) as well as HA-1–negative cell lines (U266, RR [line 6574803]) are demonstrated.