Abstract
A distinct form of X chromosome inactivation takes place during male meiosis, when the male sex chromosomes undergo a phenomenon known as meiotic sex chromosome inactivation (MSCI). MSCI is directed by DNA damage response signaling independent of Xist RNA to silence the transcriptional activity of the sex chromosomes, an essential event in male germ cell development. Here, we present protocols for the preparation and analyses of chromosome spread slides of mouse meiotic spermatocytes, thereby enabling a quick, inexpensive, and powerful cytological method to complement gene expression studies.