A DNA probe p13-1-25 is homologous to at least a portion of a hypervariable DNA region located on chromosome 19p13.2.fwdarw.19cen in the human genome. The DNA region displays extensive restrictive fragment length polymorphisms when digested with certain restriction endonucleases. Probe p13-1-25 is believed to have three closely linked lock (.alpha., .phi., .epsilon.). Loci .alpha. and .phi. each have two common alleles, whereas .epsilon. has at least 33 alleles, including a null allele. Unrelated individuals display unique fragment patterns on TaqI blots probed with p13-1-25. The probe can be used to produce a genetic "fingerprint" for establishing human identity, determining engraftment of bone marrow transplants, determining parentage, and otherwise mapping genes.