[Single maxillary central incisor and holoprosencephaly].

A holoprosencephalic female was born to a mother with a single central maxillary incisor. The newborn had microcephaly, hypotelorism, cebocephaly, palatoschisis, micrognathia, and normal chromosomes. Her brain computed tomography showed alobar holoprosencephaly. The mother was of normal intelligence and stature, and her brain computed tomography was normal. Other relatives did not have single central maxillary incisors, hypotelorism, or oral clefts. We show a further evidence of a single central maxillary incisor as an indicator of potential holoprosencephaly in the next generation, confirming an autosomal dominant trait with wide variety in penetrance and expressivity.