Here, we describe a de novo missense mutation (c.560A>G) in the human Fzr1 gene that predicts an aspartate‐to‐glycine substitution (p.Asp187Gly) in the Cdh1 protein, which results in prenatal microcephaly, psychomotor retardation, and severe epilepsy. Here, FZR1 is linked to microcephaly.