Consensus statement - Prader-Willi syndrome: Growth hormone (GH)/insulin-like growth factor axis deficiency and GH treatment

Prader-Willi syndrome (PWS) is a disabling condition characterized by hypot onia, hyperphagia, obesity, short stature, delayed or absent puberty, and m ental retardation. The syndrome complex was first described in 1956 by Dr. Andrea Prader and colleagues [1]. In the 1980s, a characteristic genetic de fect was identified involving deletion of paternal alleles at chromosome 15 q11-13 [2-6]. This occurs by deletion of alleles on the paternal copy of ch romosome 15q, an absent paternal chromosome 15q with maternal disomy, or, r arely, by mutations of the imprinting center of chromosome 15q. The estimat ed population prevalence of PWS is 1 in 15,000 live births. Short stature is a defining feature of PWS [1, 7]. Children with PWS typica lly have a gradually declining linear growth velocity beginning in early ch ildhood [8-10]. Virtually all adults with PWS are significantly below their midparental height, with an average adult height approximately 2 SD below the general population average. This degree of short stature creates a sign ificant barrier to social adaptation and performance.