A hypervariable region at the D19S11 locus.

The polymorphic locus D19S11 consists of four closely linked RFLPs: alpha, beta, delta, and gamma on chromosome 19p13.2----19cen, revealed by subclones p13-1-82 and p13-2-21 from cosmid 1-13. Here, we report that p13-1-25, an additional subclone of c1-13, reveals three insertion/deletion RFLPs, alpha, epsilon, and phi, at the D19S11 locus. In situ hybridization of p13-1-25 to metaphase chromosomes from a carrier of a 19/X translocation with a breakpoint near the centromere confirms localization of D19S11 to 19p. Studies with hydatidiform moles have generated assignments of specific restriction fragments to these three loci, and genotypic studies in three-generation families have indicated that they are closely linked. Loci alpha (also detected by p13-1-82) and phi each have but two common alleles, whereas epsilon has at least 33 alleles, including a null allele. Fifty unrelated individuals tested displayed unique fragment patterns on Taq I blots probed with p13-1-25. Applications of this probe include monitoring loss of chromosome 19 during tumorigenesis, monitoring engraftment of donor bone marrow after transplantation, testing for paternity, and mapping disease genes on chromosome 19.