RPGRIP1 and Kidney Cyst: However, the importance of Rpgrip1 in murine TZ assembling is clearly shown by the facts that the frequencies of several defects were elevated in comparison between Rpgrip1l−/− and Rpgrip1l−/−; Rpgrip1nmf247/nmf247 mouse embryos (Fig 7A) and that Rpgrip1l+/−; Rpgrip1nmf247/nmf247 mouse embryos display kidney cysts, while Rpgrip1l+/− and Rpgrip1nmf247/nmf247 mouse embryos do not (Fig 7B and C).