Induction of craniofacial malformations in rhesus monkeys (Macaca mulatta) with cyclophosphamide.

Administration of cyclophosphamide to pregnant rhesus monkeys induces two syndromes of craniofacial malformations characterized by underdevelopment of the face of different pattern depending on the timing of treatment. The first is cleft lip with cleft palate and exophthalmos. The second is a craniofacial dysmorphia with marked underdevelopment of the midfacial bones, highly arched closed palate, and either meningoencephalocele or persistent anterior fontanel. Since cleft lip and palate are among the most common malformations in man, and several human syndromes involving abnormal craniofacial development have features in common with the dysmorphic monkeys, these induced anomalies may prove valuable in investigations on the pathogenesis of such malformations and as surgical models.