Cleft palate: A genetic and epidemiologic investigation

Abstract

An examination of kindred histories of 561 Danish probands who have non-syndromic CP [cleft palate] has indicated that neither a multifactorial-threshold model nor a single major locus model is completely compatible with the data. This suggests etiologic heterogeneity for CP, which was tested with kindred data. As recommended by Smith, an attempt to define partially this heterogeneity within the CP phenotype was undertaken by grouping and comparing the kindred data. It is both reasonable and heuristic to propose that CP, as defined in this investigation, is composed of 3 groups: syndromic CP; familial CP, which appears to have an autosomal dominant component to its etiology; and non-familial CP which, by demonstrating an increasing frequency of CP and a maternal age effect, appears to be related to environmental factors which may cause CP or other malformations.