Gene for human CD59 (likely Ly-6 homologue) is located on the short arm of chromosome 11.

The CD59 (MEM-43) antigen, which probably is a human homologue of mouse Ly-6 antigens, is a broadly expressed Mr 18,000-25,000 human leucocyte surface glycoprotein recognized by monoclonal antibody MEM-43. Ten mouse-human T-lymphocyte hybrids, carrying all mouse chromosomes and a limited number of human chromosomes, were analyzed for expression of CD59 by indirect immunofluorescence and immunoblotting with MEM-43 antibody. Karyotypic analysis of the tested clones showed that the presence of human chromosome 11 correlated with the expression of CD59 in all clones tested. Three other human chromosome 11-encoded antigens, 4F2 (Trop-4), Leu 7 (HNK-1, CD57), and lymphocyte homing receptor, were expressed concordantly with CD59. A more exact localization of the gene for CD59 was obtained by the study of Chinese hamster-human cell hybrids containing short or long arm deletions of human chromosome 11. CD59 segregated with hybrids containing part of the short arm of human chromosome 11, but not with the hybrids containing the long arm. Based on these studies we assign the gene for CD59 to region p14-p13 of the short arm of chromosome 11.