Insulin-like growth factor-I deficiency caused by a partial deletion of the IGF-I gene: Effects of rhIGF-I therapy

Insulin-like growth factor-I (IGF-I) is one of the most important regulator of growth. IGF-I deficiency is associated with prenatal and post- natal growth failure and may arise primarily as a result of GH receptor/post- receptor abnormalities or defects in the synthesis and transport of IGF-I. We have previously reported a 17.2 year-old boy with severe growth retardation and undetectable serum levels of IGF-I caused by a partial deletion of the IGF-I gene. This short review will concentrate on results of a recent study which examined the effects of rhlGF-I therapy on the GH-IGF system of this patient. Similar to healthy individuals, this patient had normal IGFBP-3 but elevated ALS levels. IGF-I treatment has improved linear growth and insulin sensitivity in this patient by restoring IGF-I levels and by normalizing circulating GH, IGFBPs and insulin levels.