Monozygotic twins discordant for the Russell-Silver syndrome

Russell-Silver syndrome is a disorder of unknown cause. A number of familial cases have suggested autosomal dominant inheritance. We report on monozygotic twins discordant for the Russell-Silver syndrome. Our findings suggest that the cause of Russell-Silver syndrome is not explained entirely by genetic factors. The possible role of the intrauterine environment as an etiologic component of Russell-Silver syndrome is discussed.