Further studies on the genetic heterogeneity of cebocephaly.

Abstract

The detailed morphological description of 4 infants with cebocephaly, 3 of which were karyotyped (one with D trisomy and 2 with normal karyotypes), are presented. Analysis of all cytogenetically studied cases with this malformation reveals that cebocephaly with a normal karyotype may resutt from more than 1 mutant gene, and so it may be accompanied by different extracranial abnormalities. An absence of visceral malformations does not exclude chromosomal aberrations; thus the 18p- syndrome, where cebocephaly is frequent, may have no visceral abnormalities.