The bovine pancreatic spasmolytic polypeptide gene maps to syntenic group U10: implications for the evolution of the human breast cancer estrogen inducible locus.

Recently, homology has been reported for pS2, a protein expressed in many human breast cancers, and a hormonogastric protein known as pancreatic spasmolytic polypeptide (SPP; formerly designated as PSP). The breast cancer estrogen inducible locus (BCEI), which encodes pS2, maps to human chromosome 21 (HSA 21). The SPP locus has not been mapped in humans. Several loci from HSA 21 have been mapped in cattle to syntenic group U10, but a BCEI bovine homolog was not detected. If a bovine BCEI locus does exist, map comparisons predict BCEI will reside on syntenic group U10. The assignment of bovine SPP to syntenic group U10 supports the postulated evolutionary relationship between BCEI and SPP.