African pygmy mice: Females are XY ... researchers find out why
Wednesday, February 24, 2010 - 23:14
in Biology & Nature
In a great majority of cases, the Y chromosome determines sex in mammals. The African pygmy mouse M. minutoides is an exception to this rule. In this species, which is a close relative of the house mouse, it is the X chromosome that determines sex. Researchers in France have just identified this unexpected case of sex determination. These scientists have demonstrated a particular chromosomal rearrangement on the X chromosome of this mouse. This work should provide a clearer understanding of how classic sex determination functions in mammals.