The presence of the A*24020102L allele is implicated in one donor from the CBMD who serologically was typed as A2; B44, B55; Cwl, Cw7. The DRB4*01030102N allele was identified in one healthy donor and in one patient with MDS during routine HLA class II DNA typing. The DRB4*01030102N allele was identified in the patient's father, who had CML, and was associated with the HLA-A3-B7-Cw7-DRB1*0701-DQB1*0303 haplotype, which is common for European populations. In order to avoid mistyping, both techniques, serology and molecular biology must be used for HLA typing, especially for cases where just one antigen appeared to be present using serological methods.