Lung hypoplasia may manifest in patients losing one IGF-1R gene copy for chromosome 15 deletion, along with other disorders such as intrauterine growth retardation (IUGR), microcephaly, abnormal face and ears, micrognathia, highly arched palate, renal abnormalities, failure to thrive, developmental delay, and mental retardation [35]. Here, IGF1R is linked to fetal growth restriction.