Partial duplication of the long arm of chromosome 15: confirmation of a causative role in craniosynostosis and definition of a 15q25-qter trisomy syndrome.

A syndrome of mental retardation and multiple congenital anomalies, including craniosynostosis and overgrowth, was observed in two related individuals from a large kindred. Both of them carried a 15q25.1-qter trisomy associated with a subtle 13qter monosomy resulting from unbalanced segregation of a familial t(13;15)(q34;q25.1) translocation. Reportedly, a further individual in this kindred has the same condition. The present report confirms previous claims that gene(s) in the distal 15q region play a role in suture formation. At the same time it adds new data to the delineation of a 15q25-qter trisomy syndrome.