For example, Lp/grainyhead-like transcription factor 3 (Grhl3) doubly heterozygous mutants develop severe spina bifida (Stiefel et al., 2007; Caddy et al., 2010; De Castro et al., 2018), while Lp/cordon-bleu WH2 repeat (Cobl) mutants exhibit exencephaly (Carroll et al., 2003). The gene discussed is GRHL3; the disease is spina bifida.