Among the 11 patients with MRI abnormalities (including periventricular leukomalacia or corpus callosum dysgenesis), IGF-1 levels (35.96 ± 15.53, [range 17.20–66.20] ng/mL) were lower than those in patients with non-structural etiologies (49.38 ± 16.46, [range 19.90–79.30] ng/mL), though this difference did not reach statistical significance (p = 0.099). The gene discussed is IGF1; the disease is Dysplastic corpus callosum.