THE Y-CHROMOSOME - A GRAVEYARD FOR ENDOGENOUS RETROVIRUSES

We have isolated 20 different human endogenous retroviruses (ERV) rela ted to ERV3, Hsrirt and Humer 4-1. Phylogeny and the presence of these ERV among different primates were determined by computer and Southern blot analyses, Preferential localization of ERV to the human, chimpan zee and orangutan Y chromosomes among the low-copy-number ERV is demon strated. The reason for this accumulation of ERV on the strongly heter ochromatic Y chromosome is probably mediated by (i) the absence of rec ombination of the Y chromosome that makes it more difficult for sequen ces to be lost, and (ii) integration of retroviruses in heterochromati c regions is less harmful to the organism. If ERV located on the Y chr omosome are transcribed and translated to peptides, such peptides coul d be potential HY-antigens.