Localization of a second NM23 gene, NME2, to chromosome 17q21-q22.

NM23 is a candidate tumor suppressor protein and has recently been identified as an NDP kinase. The expression of NM23 is inversely related to the metastatic potential of tumor cells. Two NM23 genes, NME1 and NME2, that code for the A and B chains of the kinase, respectively, have been cloned. To determine the human chromosomal location of the NME2 gene, we have analyzed DNA from rodent-human cell lines and hybrid cell lines containing portions of chromosome 17 by a combination of PCR amplification and Southern hybridization. The NME2 gene was mapped to the chromosome region 17q21-q22, the same region in which the NME1 gene has been localized. This region is linked to the early onset breast/ovarian locus (BRCA1) and allelic deletions of NME1 have been associated with metastatic potential of colorectal carcinomas.