They have not really proven there is a genetic link but they are pretty sure genetics are involved in some way. In my case my brother is on the spectrum and then both my children are.
I have met people with no family history of ASD at all that have an autistic child as well so it is just not a proven science yet.

As far as the testing a psychologist or neurologist can make the call on a diagnosis by testing which is similar to what they do for children but different as an adult. My advise is the same when I am asked about all the genetic testing for children and that is not to pay out of pocket for extensive testing because insurance doesn't cover it all. Also you are not likely to get an answer that is going to help you in any way.

Let's put it this way, let's say you found out that genetic testing proved where the autism came from, how does that help with the treatment for your child much less an adult. You money is better spent on treatments and therapies that actually help rather than to chase an answer you may not get.

If you are looking for the DX to apply for SSI or something like that then keep in mind they go by how much money you make and if your child already gets SSI they will just take away from their amount to give to the adult. I know this first hand because my wife has a lot of medical issues and she won't get disability because it gains us nothing.

I don't know how useful it is to be diagnosed for ASD as an adult. Will it change anything if your husband or you have lived long enough without knowing about it? The only application may be is if want to have more kids but you already have a kid with ASD so you have your answer.

We didn't have to pay for genetic testing and our daughter is one of the few kids with ASD who has a genetic issue- a duplicated set of genes. That's weird because my wife and I are from different continents and different races so how did we have the same genes and manage to have a daughter with ASD. Pretty rare so our daughter is different even from a lot of other ASD kids.

"Our kids have insurance, but neither of us do." You don't have health insurance? Are you paying that Obamacare tax for not having health insurance? It will go up.

Sorry a lot of "I guess" thrown in there lol. It's still too early for me :)

No we are just between insurance right now. We couldn't afford our old insurance because the rates went up and we have to wait for the enrollment time through my husbands work insurance. I know getting a diagnoses for my son opened up so many doors as far as getting different therapies or help for him. Most places you go want that diagnosis. Figured I could get my hubby some of the help he never received as a kid and could still use to this day or possibly different medications he might want to try if any at all? Or maybe just some understanding or validation of why he is the way he is or does the things he does or has certain difficulties doing everyday things. I honestly would like to get evaluated for the same reason. Not extremely necessary I guess, just more of a validation or piece of mind I guess. Kind of hard to explain I guess. Just something I've been wondering since I was a kid and now that my son has autism and I know more about it, it would just kind of make more sense to me about my husband and myself.just a thought and throwing it out there to get some feedback of people that have might ha e experienced this.