X-inactivation

X-inactivation is a natural process in female mammals where one of the two X chromosomes in each cell is randomly turned off to balance gene expression with males, who have only one X chromosome. This inactivation occurs early in development, with the cell "choosing" which X to deactivate. The inactive X forms a tightly packed structure called a Barr body. Once inactivated, it remains silent in all the daughter cells. This process ensures that females, like males, have a similar amount of X-linked gene products, maintaining genetic balance across sexes.