Clinical and genetic features of Van der Woude syndrome in two large families in Brazil.

OBJECTIVE: This report describes the clinical and genetic features of two large and unrelated families with Van der Woude syndrome in Brazil, emphasizing the range of anomalies found within and between the families. PATIENTS: Family 1 included 54 descendants spanning five generations, with 12 (22.23%) individuals manifesting Van der Woude syndrome. In family 2, examinations comprised 17 descendants distributed over four generations, and 8 (47.06%) people presented features of Van der Woude syndrome. RESULTS: In family 1, the first two generations were not affected, but the other three generations had affected members showing a unique association of lip pits and cleft lip/palate with equilibrated gender distribution. In family 2, all generations were affected, and the clinical expression of disease was heterogeneous, including members with isolated clefts, isolated lip pits, and association of cleft lip/palate with lip pits. In both families, affected members transmitted their traits to descendants in an autosomal dominant mode of inheritance with apparent low penetrance in family 1, but high penetrance in family 2. Patients were treated surgically by cheiloplasty and/or palatoplasty with satisfactory results. CONCLUSIONS: Van der Woude syndrome was transmitted by an autosomal dominant pattern with variable expressivity and penetrance and equilibrated gender distribution. Physicians should be aware of the variety of malformations that can be associated with Van der Woude syndrome. Genetic counseling in Van der Woude syndrome affected families is important, because a high percentage of descendants can have some kind of clefting.