SMAD2 and autosomal dominant polycystic kidney disease: For ADPKD, previous studies have already shown that screening for IA can be cost-effective,29,30 whereas for LDS, screening is advised based on expert opinion.31 Furthermore, the finding that carriers of rare, damaging variants in PKD1 and SMAD2 were at increased risk of IA even in the absence of a diagnosis of ADPKD or LDS, suggests the potential for genetic screening in ASAH patients, since their family members may be at risk of IA/ASAH if they are carriers as well.