Familial short stature with IGF-I receptor gene anomaly

Type I insulin-like growth factor receptor (IGF-IR) is widely expressed across many cell types in fetal and postnatal tissues. The activation of this receptor after the binding of secreted IGF-I and IGF-II promotes cell differentiation and proliferation. IGF-IR has an important role in normal fetal and postnatal growth and development. IGF-IR gene anomalies presenting with intrauterine and postnatal growth retardation have recently been reported in some families. Familial short stature with IGF-IR gene anomaly is considered rare, and the clinical condition and features remain unknown. IGF-IR gene anomaly such as heterozygous IGF-IR mutation or haploinsufficiency of the IGF-IR gene should be investigated in those patients presenting with 1) low birth weight and birth height (< -1.5 SD), 2) a familial history of low birth weight, 3) a normal or increased IGF-I level, 4) a normal or increased GH response to the GH stimulation test, and/or 5) less response to GH treatment than common small for gestational age (SGA) short-stature patients. In this review, we provide an overview of current knowledge of familial short stature with IGF-IR gene anomaly.