Several overlapping amplicons were used to obtain the sequence of genomic DNA covering most of the coding regions of KIR3DL1 and KIR3DS1 from a family and 77 bone marrow transplant patients and their unrelated donors. Alleles 3DL1*00101 and *002 were most frequently observed in addition to 12 other known 3DL1 alleles. A single 3DS1 allele, 3DS1*01301, was identified in the 31 of 32 individuals carrying this gene. Two new alleles, 3DL1*01702 and 3DS1*058, were characterized. Three samples appeared to carry the duplicated killer cell immunoglobulin-like receptor (KIR) haplotype observed in other studies based on the presence of 3DS1 and two 3DL1 alleles. Additionally, one sample appeared to carry a novel KIR haplotype containing one 3DL1 and two 3DS1 alleles.