Causes of HAE
HAE inheritance is autosomal dominant. It means that the genetic disease occurs when children inherit one copy of the defective gene from one of their parents. For instance, if children have either their mother or their father with a defective gene, they may have a 50% possibility of inheriting this defective gene. However, HAE would still occur in people whose parents do not have a defective gene or HAE. In these cases, the gene may by spontaneously mutated. Around 1 out of 4 people with HAE has their C1 inhibitor gene being mutated randomly. [3]