Dr. Garg and colleagues have also ascertained the genetic basis of mandibuloacral dysplasia (MAD), which is a rare, genetically and phenotypically heterogeneous, autosomal recessive disorder characterized by skeletal abnormalities including hypoplasia of the mandible and clavicles, and acro-osteolysis, cutaneous atrophy and lipodystrophy. Two genetic defects, one in the lamin A/C gene and the other in the enzyme, zinc metalloproteinase (ZMPSTE24) which processes lamin A to its mature form have been identified in patients with MAD.  Some of these patients have features of accelerated aging or Progeria and these studies are expected to help us understand the aging process in humans.