The present study reports on two siblings of different sex, affected with a condition corresponding to Mohr syndrome. Characteristic symptoms such as epicanthic folds, a broad and flattened nasal root, a lobulated and hamartomatous tongue, poly- and syndactyly on both hands and feet, doubling of the big toes with less frequent features such as marked psychosomatic retardation and overall hypotony have been observed. All the cited anomalies have been of importance in the differential diagnosis. Difficulties associated with classification of new syndromes and the importance for practical clinical genetics of distinguishing between them are discussed.