Chromogranin A/secretory protein I (CgA) is a glycoprotein that is stored and released along with peptide hormones and neurotransmitters from several tissues, although its exact function is not known. A cDNA (gene symbol CHGA) clone was used as a probe in Southern blot analyses of human-rodent somatic cell hybrid DNAs. Discordancy analysis allowed confirmation of the assignment of the gene to chromosome 14. These results were extended using in situ chromosome hybridization, and a signal was found at 14q32. BglII digestion of genomic DNA from 28 unrelated Caucasian individuals probed with CHGA detected a two-allele RFLP with allelic frequencies of .34 and .66.