The gene for the mouse recoverin protein (23 kDa photoreceptor-specific protein, S-modulin, or the Cancer-Associated Retinopathy protein) was recently assigned to mouse chromosome 11, closely linked to trp53. In this paper, the human gene for recoverin was localized to human chromosome 17 by Southern analysis of restriction digests of the DNA from mouse/human somatic cell hybrids. Using a 7 kb subclone of the human recoverin gene, a positive fluorescence in situ hybridization signal was demonstrated near the terminus of the short arm of chromosome 17 at position p13.1. The mapping of recoverin to this region of human chromosome 17, which contains a number of cancer-related loci, suggests a possible mechanism by which cancer-associated retinopathy occurs in humans.