Selection of Less-Prevalent Overgrowth Syndromes

Abstract

In addition to the major generalized overgrowth syndromes described in this text, there is a rich case report literature on less common and less well-defined disorders in which overgrowth has been noted. The latter disorders are described concisely in this chapter. In some cases there have been multiple cases reported and the causative gene or genomic alterations have been identified. Although others are suspected to be genetic or genomic disorders, no specific cause has been implicated. These disorders are sufficiently uncommon that a body of literature has not accumulated and the manifestations are sufficiently variable that most are not clinically recognized. In addition, the chapter takes note of those environmental influences that can produce overgrowth. Maternal diabetes is the most common of the environmental influences that cause overgrowth during fetal life and carries a several-fold increased risk of malformations.