The oral-facial-digital syndromes (OFDS) have in common minor facial and oral anomalies (including tongue lobulation and/ or hamartomas, accessory frenula, and alveolar anomalies) and variable digital defects such as polydactyly. The classification based on the presence of additional findings [Toriello, 1988, 1993] is not perfect, as many reported examples of a particular OFDS have some other condition. Here we describe six children, all diagnosed as having OFDS IV (OFDS with tibial defects), whose manifestations illustrate the apparent genetic heterogeneity.