ADAMTS2 and brain aneurysm: ,65 The molecular basis for these phenotypic differences remains unknown, but the observation of a much more severe skin phenotype, and of dEDS symptoms that are not or to a lesser extent observed in aEDS patients, like bladder diverticula and cerebral aneurysm, suggests a major role for ADAMTS2 in the homeostasis of the affected tissues, possibly through cleaving other substrates.