Over the last few decades, typing for the human leukocyte antigen (HLA) has become critical for bone marrow transplants. Research has also indicated that individuals with certain allelic genotypes may be at a higher risk for developing diseases affecting the immune system, and therefore rapid tests to identify the numerous allelic differences are needed. Such tests must allow for the detection of the various alleles present in a 4-Mbp region on the short arm of chromosome 6. The area comprises three class regions: class I, which includes HLA-A, HLA-B, and HLA-C genes; class II, containing the HLA-D genes; and class III, composed of numerous protein coding genes responsible for a range of functions (1,2).