Repression of Endogenous Retroviruses Prevents Antiviral Immune Response and Is Required for Mammary Gland Development

Investigators demonstrated that the loss of the lysine 9 of histone H3 methyltransferase G9a in the mammary epithelium resulted in de novo chromatin opening, aberrant formation of the mammary ductal tree, impaired stem cell potential, disrupted intraductal polarity, and loss of tissue function.