Generation of prolactin-inducible protein (Pip) knockout mice by CRISPR/Cas9-mediated gene engineering.

Prolactin-inducible protein (PIP) is a multifunctional glycoprotein that is highly expressed and found in the secretions of apocrine glands such as salivary, lacrimal, and sweat glands including the mammary glands. PIP has been implicated in various diseases, including breast cancer, gross cystic disease of the breast, keratoconus of the eye, and the autoimmune Sjögren's syndrome. Here we have generated a knockout (KO) mouse using the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRSPR-associated (Cas)9 system.