In general, the more diverse of genes an individual inherits, the less likely they are to inherit copies of the same mutation.
Autism, anxiety, and ADHD are generally thought to not be connected to genetic inheritance. Anxiety or ADHD may show up more prevalently among some families, but often have more to do with environment, diet, emotional processing, emotional security, relationships, etc than being directly inherited.
Autism is complex and not totally understood yet, but there's definitely an immune system element to it that is thought to be influenced by many different environmental, dietary, microbial, and even birth factors. Genetics don't appear to be a main driving force in the development of autism.
Trauma can be passed on generationally and affect not just emotions but physical elements as well, but it is not totally understood, and it has a lot to do with individuals involved. Even when people inherit certain genes predisposing them to serious conditions, there are a variety of factors within the individual that determine whether or not those genes get activated or not.