Thanks for your help, everyone. I've talked to a lot of doctors and they say that the genetic tests (for the less common genes, so not including Fraxa or TS) are used to help direct treatment. But they can only identify known genes in 10-15% of cases so its' not clear how helpful they are so far.
If you're interested in reading my article when it comes out in a few months, let me know. Otherwise, best wishes to you all!
Hannah