THE LINKAGE OF GENES FOR THE HUMAN INTERFERON-INDUCED ANTIVIRAL PROTEIN AND INDOPHENOL OXIDASE-B TRAITS TO CHROMOSOME G-21

13 independent mouse-human somatic cell hybrid clones derived from ß-propiolactone-inactivated Sendai stimulated cell fusion of human cells with mouse cells were tested for their sensitivities to human and mouse interferon. All of them were protected by mouse interferon and only six of the clones were protected by both human and mouse interferon. Only the six that were protected by human interferon were shown to express the human dimeric form of indophenol oxidase. Complete chromosomal analysis of the clones indicated human chromosome G-21 to be the only human chromosome in common for the six clones which had both phenotypes present. Nine subclones were derived from one of the clones expressing both phenotypes. Eight of the nine subclones were shown to retain both phenotypes, whereas one subclone lost both. Chromosomal analysis of the subclones indicated the loss of chromosome G-21 from the subclone which lost both phenotypes. It is apparent from these findings that the gene(s) for indophenol oxidase (IPO-B) and the gene(s) for the antiviral protein are syntenic and that they are linked to human chromosome G-21.