Its frequency is estimated at 1 per 4000 live births.
Studies indicate that nearly half of individuals with VCFS have mental retardation.
A nasal speech tone is observed in the vast majority of individuals with VCFS as well as difficulties with articulation whose origin is assumed to be the cleft palate and pharyngal hypotonia. For example, Shprintzen et al. Here at Stanford, we feel that the behavioral and cognitive traits of VCFS can best be understood through an integrative approach combining clinical observation of children and adolescents, molecular biology, and structural and functional . The Division of Child and Adolescent Psychiatry and Child Development at the Stanford University School of Medicine has been conducting a major research project on VCFS since 1997. A report from the evaluation will be provided upon request.