Linkage map of a region of human chromosome band 11q13 amplified in breast and squamous cell tumors.

DNA amplification involving markers on human chromosome band 11q13 is a consistent feature of several major cancers, notably adenocarcinoma of the breast and squamous cell carcinoma of the head, neck, lung, and esophagus. Since the presence of the amplification may be clinically significant, by defining a subset of patients at increased risk, it is important to establish which of the several genes on the amplified DNA provides the selective force. Here we describe a physical map of the centromeric end of the amplified DNA as it exists in a particular squamous carcinoma cell line (UMSCC2) and establish an unambiguous order for several known markers in the region, including pMS51/D11S97, pHB159/D11S146, BCL1, PRAD1/D11S287, HSTF1/FGF4 and INT2/FGF3. Significantly, PRAD1 is within 120-150 kb of the BCL1 translocation breakpoint and the data identify a new CpG island (D11S814) between PRAD1 and HSTF1. The ordering of the HSTF1 and INT2 genes and the clustering of CpG islands in the region have important implications in assessing whether the frequently observed amplifications at 11q13 are centered on one or more genes.