These studies demonstrated that genetic deletion of DDR1 also did not slow cyst growth or preserve kidney function in Pax8rtTA; TetO-Cre; Pkd1fl/fl mice; H&E staining of kidney sagittal sections, kidney/body weight ratio, and BUN were similar between DDR1-/-; Pax8rtTA; TetO-Cre; Pkd1fl/fl and DDR1+/+; Pax8rtTA; TetO-Cre; Pkd1fl/fl mice (Fig 4). This evidence concerns the gene DDR1 and cyst.