PRICKLE1 and X-linked retinoschisis: Previous studies (Afzal et al., 2000a; Afzal et al., 2000b; Ali et al., 2007; Butler and Wadlington, 1987; Patton and Afzal, 2002) suggested that the tissue outgrowth and craniofacial defects in Prickle1 mutants were reminiscent of human Robinow syndrome (RS).