PIK3R1 and fetal growth restriction: The phenotype is correspondingly the “inverse” of vascular malformations and overgrowth, including intrauterine growth restriction, lipoatrophy, and insulin resistance/diabetes.27 Of note, very rare reports of phenotypic overlap have been described between APDS2 and SHORT syndrome.28 In principle, these findings suggest that there are largely distinct spectra of PIK3R1 variants associated with these three disorders.