Individuals with holoprosencephaly (HPE) and limb reduction defects have been ascribed historically to a variety of syndromes with overlapping phenotypic features. As such, these patients are challenges for clinicians and researchers alike. In an effort to better understand this association, we reviewed our autopsy records and identified five cases of HPE with reduction defects of the limbs and other anomalies. One case appears to be the third reported instance of Steinfeld syndrome, while others represent microgastria-limb reduction sequence, VATER/VACTERL association, and an additional unique condition characterized by HPE, rhombencephalosynapsis, absent left radius, first metacarpal, and thumb, and congenital heart disease. The phenotypic heterogeneity inherent in these patients continues to complicate diagnosis, which will hopefully be simplified by continuing delineation at morphologic and especially genetic levels.
2005 Wiley-Liss, Inc.