Epidemiological analysis of the schisis association in the Spanish registry of congenital malformations.

Since its description by Czeizel [1981: Am J Med Genet 10:25-35], there has been general acceptance of the schisis association as a distinct entity although, to the best of our knowledge, no other epidemiological study has confirmed its existence. Here we present an epidemiologic study on schisis defects and their associations with each other in children with and without blastogenetic defects. This study demonstrates that most cases represent the dysmorphogenetic response of the primary developmental field.