RXRA and Stillbirth: Similarly, embryonic lethality has been observed in Rdh10, double RXR or RAR α/β, α/γ, and β/γ mutants (Lohnes et al., 1994; Mark et al., 2006), stillbirths in RXRα (Mascrez et al., 2009), and neonatal lethality in Aldh1a3 mutant mice (Dupé et al., 2003; Molotkova et al., 2007; Sandell et al., 2007).