Autosomal dominant inheritance of the DeMyer Sequence.

Holoprosencephaly (HPC) may be an isolated trait or may be associated with other craniofacial defects. As an isolated trait, HPC has been reported to be inherited as an autosomal recessive, while autosomal dominant inheritance has been reported for sequences or syndromes in which HPC occurs. This paper presents a family in which several people have variable combinations of craniofacial defects. The most severely affected relatives have HPC, while others have only mild facial dysmorphia and decreased bitemporal diameters. One relative has a single central incisor in the maxilla. The pattern of defects in this family is inherited as an autosomal dominant. Other families with the reported pattern of defects, including single central incisors as minimal manifestations, are cited. Because HPC is found only occasionally in the pattern of defects, the term DeMyer Sequence is proposed as a more appropriate designator than the more commonly used Holoprosencephaly Sequence.