A number of mouse models with severe symptoms of CS (‘NER progeria’ in mice), display apparent alterations in systemic metabolism during post-natal development, including loss of adiposity, perturbations of the post-natal GH-IGF-1 axis and hypoglycemia contributing to death before weaning.20 Using the CX mouse model that survives weaning with high penetrance,19 we first characterized changes in adiposity, glucose and lipid homeostasis as markers of whole-body energy metabolism. This evidence concerns the gene IGF1 and Hypoglycemia.