CAV1 and congenital generalized lipodystrophy type 4: Congenital generalized lipodystrophy type 3 and congenital generalized lipodystrophy type 4 are due to genetic mutations in caveolin-1 and cavin-1, respectively, both of which are crucial for the formation of caveolae, specialized microdomains of the cell plasma membrane that activate various signaling pathways.