Allele loss on short arm of chromosome 17 in breast cancers.

Tumour and blood leucocyte DNA from a consecutive series of patients with primary breast cancer was probed to detect deletions at six polymorphic loci in tumour tissue. The highest frequency of allele loss (61%) was found with the probe YNZ22, which detects a sequence on the short arm of chromosome 17 (at p13.3). The previously reported loss of alleles at the Harvey ras locus (11p14) in about 20% of breast tumours was confirmed. The putative breast tumour suppressor gene on 17p may be the same as that already noted for colon and lung cancers and it is suggested that deletion of this gene is one of a cumulative series of lesions involving genetic changes in the evolution of breast cancer. The findings identify chromosome 17p as a candidate region for linkage studies in breast cancer families.