CMM is a rare genetic disorder that is characterized by involuntary movements on one side of the body induced by intentional movements on the opposite side (Galléa et al., 2011; Cox et al., 2012; Welniarz et al., 2017a) as the result of mutations in the DCC, RAD51, and NTN1 (netrin-1) genes (Srour et al., 2010; Depienne et al., 2012; Méneret et al., 2017). Here, RAD51 is linked to familial congenital mirror movements.