CDY Background Information CDY, a gene family expressed exclusively in the testis, localizes to a region of the Y chromosome frequently deleted in infertile males. CDY protein contains two functional domains, an N-terminal chromodomain, possibly functioning in heterochromatin interactions, and also a C-terminal domain which resembles enoyl-CoA-isomerase, a protein involved in fatty acid oxidation. Furthermore, CDY acts as a histone acetyltransferase, with strong preference for histone H4, a process required for the histone to proamine transition in spermatogenesis, consistent with the association with male infertility.
