The proopiocortin (adrenocorticotropin/beta-lipoprotein) gene is located on chromosome 2 in humans

The proopiocortin gene is located on chromosome 2 in humans. A 13-kb DNA fragment containing proopiocortin gene sequences was identified in human cells while proopiocortin-related genes sequences of 9.8 and 6.2 kb were present in mouse cells. In human-mouse cell hybrids which contained reduced numbers of human chromosomes and a complete set of mouse chromosomes, the 9.8- and 6.2-kb fragments were always present while the 13-kb fragment segregated with human chromosome 2 and the chromosome 2 enzyme markers acid phosphatase-1 (ACP1), malate dehydrogenase-1 (MDHI), and isocitrate dehydrogenase-1 (IDH1). Analysis of a single cell hybrid with a broken chromosome 2 indicates that the proopiocortin and ACP1 genes are closely linked and in the distal region of the short arm of chromosome 2.