Sublocalization of a locus at 3p21.3-23 predisposing to hereditary nonpolyposis colon cancer.

Hereditary nonpolyposis colon cancer (HNPCC) is a heterogeneous disease caused by at least three different genes on chromosomes 2 and 3, and one or more additional chromosomes. We used 19 dinucleotide markers in order to sublocalize further the 3p locus linked to HNPCC, and to order the markers into one map resulting in a panel of markers suitable for linkage studies. Human chromosome 3 mouse hybrids were used to determine the chromosomal position of the markers. Haplotype analysis in two families where the disease is linked to chromosome 3p21-23 was used in order to sublocalize further the region in which the gene is located. Based on our results, the gene has now been localized to the region 3p21.3-23.