CDKL5 and nutritional deficiency disease: Interestingly only one study included FOX1 gene mutation together with MeCP2 and CDKL5 mutations, and two studies reported patients with CDKL5 mutation and MeCP2. The main endocrinopathies described in the selected studies were malnutrition and bone alterations (8/24) followed by puberty onset disorders and obesity (7/24).