PITX2 and dilated cardiomyopathy: Nonetheless, the morphologic and functional changes described earlier and herein for the three Rgs knockout genotypes are consistent with the postulation that abnormal G protein signaling is causally involved in nonischemic cardiomyopathy of the left ventricle or dilated cardiomyopathy (DCM) (Gava et al., 2023; Wang et al., 2023).