How X chromosome is inactivated in female mammals?
One of the X chromosomes is completely and permanently inactivated during a female's early development in the womb. Research into mice has shown that a ribonucleic acid (RNA) molecule called Xist plays a pivotal role in the process. Several hundred copies of this molecule attach themselves to one of the two X chromosomes, these RNA molecules dock onto other molecules which then inactivate the chromosome. Spen gene is very important for X chromosome inactivation.
Ref: Asun Monfort et al., 2015, Cell Reports.
DOI: 10.1016/j.celrep.2015.06.067
