Patients generally showed proportionate short stature (−2.8 ± 0.5 SDS), low serum IGF-I (−1.6 ± 0.7 SDS) with considerable variability, a normal stimulated GH response (performed in 15), and 4 patients suffered from failure to thrive with low appetite in infancy. This evidence concerns the gene IGF1 and Failure to thrive.