Pre- and postnatal growth failure with microcephaly due to two novel heterozygous IGF1R mutations and response to growth hormone treatment.

Aim: To explore the phenotype and response to growth hormone in patients with heterozygous mutations in the insulin-like growth factor I receptor gene (IGF1R).

Methods: Children with short stature, microcephaly, born SGA combined with biochemical sign of IGF-I insensitivity were analysed for IGF1R mutations or deletions using Sanger sequencing and Multiple ligation-dependent probe amplification analysis.

Results: In two families, a novel heterozygous non-synonymous missense IGF1R variant was identified.