Homozygous or compound heterozygous mutations in fibulin-4 (<i>FBLN4</i>) lead to autosomal recessive cutis laxa type 1B (ARCL1B), a multisystem disorder characterized by significant cardiovascular abnormalities, including abnormal elastin assembly, arterial tortuosity, and aortic aneurysms.
We used a mouse model of postnatal ascending aortic aneurysms ( Fbln4<sup>SMKO</sup>; termed SMKO [SMC-specific knockout]), in which deletion of Fbln4 (fibulin-4) leads to disruption of the elastin-contractile units caused by a loss of elastic lamina-SMC connections.