If a father or mother in the proband is known to have the pathogenic variant discovered during the proband, the risk on the sibs of inheriting the pathogenic variant is fifty%. As a result of lessened penetrance, sibs who inherit the pathogenic variant might or might not produce aHUS (see https://airhandlingunitahuhire33321.fireblogz.com/63191361/air-handling-unit-ahu-hire-options