Polysyndactyly With Cardiac Malformation

Clinical Features

Bonneau et al. (1983) described a family in which normal, unrelated parents had 3 children, all with polysyndactyly and a complex cardiac malformation: atrial and ventricular septal defects in 1 and cor biloculare in a second. The hexadactyly was of the first toe type (duplication of the great toe). The third and fourth fingers showed syndactyly. Hydramnios was evident by the beginning of the third trimester in each pregnancy. Karyotype was normal. One child lived 5.5 months; the other 2 were stillborn.

Rajab (1997) described the Bonneau syndrome in 2 male sibs in Oman.

Stoll and Gasser (2003) reported a 3-year-old girl, born of first-cousin parents, who had multiple congenital anomalies at birth, including left ptosis, hypertelorism, anteverted nares, large fontanel, long philtrum, nail hypoplasia, polysyndactyly, single transverse crease, complex cardiopathy, and hepatic cysts. Another pregnancy of the mother was terminated; examination of the male fetus revealed facial anomalies, small penis, polysyndactyly, and ventricular septal defect with aortic dextroposition, dilation of the right heart, and small left heart. Histologic examination of the liver showed an anomaly of the ductal plate characterized by multifocal cystic nonobstructive dilation of the intraheptic bile ducts with portal tract lesions. Stoll and Gasser (2003) noted that this family lends support to autosomal inheritance of this condition.

Olgun et al. (2009) described a 2-month-old Turkish girl, born of consanguineous parents, with facial dysmorphism, complex cardiac anomalies, polysyndactyly, dysgenesis of distal extremities, and bilateral multiple renal cysts.

Inheritance

The occurrence of Bonneau syndrome in sibs and in consanguineous families supports autosomal recessive inheritance.