On the contrary, in Restrictive Dermopathy (RD) and Mandibuloacral Dysplasia type B (MADB), prelamin A accumulation arises from mutations of the ZMPSTE24 metalloproteinase [12,13], while, in Familial Partial Lipodystrophy (FPLD) and Mandibuloacral Dysplasia type A (MADA), the underlying cause of prelamin A accumulation is unknown [7,14]. This evidence concerns the gene ZMPSTE24 and familial partial lipodystrophy.