Silver-Russell Dwarfism and Cystic Fibrosis in a Twin

A 6-year-old male twin with cystic fibrosis (CF) and the Russell variant of the Silver-Russell dwarf was studied as were his normal twin sister, parents, and two other siblings. For the first time, detailed craniofacial measurements describing the craniofacial dysostosis common to the Silver-Russell syndrome were made and analyzed. Chromosomes, studied by the Giemsa-banding technique, were normal in the patient and other family members. The patient had markedly increased atd angles and whorls on all fingers. Growth hormone and plasma and urinary gonadotropin levels were normal. It is postulated that the cause of the Silver-Russell syndrome is genetic, since it is concordant in monozygotic twins, nonconcordant in fraternal twins, and occurs in siblings from parents with a common ancestor. The combination of Silver-Russell dwarfism and CF may be coincidental.