genetics increase one's risk of PTSD, as well PTSD can be developed through vicarious trauma.
Misophonia condition appears to have the following in common with PTSD;
Anger , muscle tension, feeling of stress, loss of concentration
in reaction to specific sounds
If a parent has misophonia does that increase the risk for the child to develop the condition as well?
Are there any known cases that both parent and child have misophonia ?
I can't find research on whether it has been confirmed if misophonia is a stream of PTSD. Or if it has been confirmed if it is genetic.