If a dad or mum in the proband is understood to have the pathogenic variant recognized from the proband, the risk on the sibs of inheriting the pathogenic variant is fifty%. As a result of minimized penetrance, sibs who inherit the pathogenic variant might or might not establish aHUS (see https://watercooledchillers26036.total-blog.com/how-ahu-s-can-save-you-time-stress-and-money-57750971