If a parent of your proband is thought to have the pathogenic variant determined within the proband, the risk into the sibs of inheriting the pathogenic variant is 50%. As a consequence of decreased penetrance, sibs who inherit the pathogenic variant might or might not develop aHUS (see Penetrance). Modifiers https://boilerrental93603.blogzet.com/detailed-notes-on-air-handling-units-ahus-47087073