Congenital generalized lipodystrophy (CGL) is divided into four subtypes. Type 1 is mainly caused by mutations in AGPAT2 gene, subtype 2 by BSCL2 mutations, type 3 by CAV1 mutations and type 4 by CAVIN1 mutations.
Patients with CGL show a near total absence of body fat which starts either at birth or shortly after. There are also metabolic abnormalities. Type 1 CGL shows loss of metabolically active adipose tissue. Type 2 CGL has a general absence of adipose tissue. Patients with type 3 CGL show vitamin D resistance, hypocalcemia, hypomagnesemia and have a short stature. Patients with type 4 CGL show myopathy, skeletal abnormalities, cardiac arrhythmias, pyloric stenosis and gastrointestinal motility problems.