Ethnic background may be a better way to go.

My dad had PD and the fact that our background is Ashkenazi Jew is NOT good for me.

My father changed his surname, and I'm the first in our family with the new name. So I laugh when family tree people tell me about my relatives.

Of course, in any such study, I'd use my dad's original surname. And my mother's.

I've always informed my neuros of my ethnic background. They previously thought that late onset is NOT genetic, but were proven wrong in 2005 or 2006.

I had told my neuro about a 2003 study with Poles, and there was a genetic connection in the study. She disregarded it but I was certain that it was relevant. Honestly, I've always been ahead of ALL my neuros (including MDS), because I don't fit in a neat box. Varied symptoms (and pathology) are often typical of LRRK2 mutations.

By the way, my neuro said it would be fine if I used mucuna pruriens because it is natural, even though she'd never heard of it. I mentioned if after she mentioned fava beans. She said several incorrect things, too so I lost all respect for her.

One example: she said it could not be dopa responsive dystonia (I thought maybe my dad was misdiagosed) because:

I respond to Artane (trihexyphenidyl), and DRD responds to l-dopa. I said those responses are not mutually exclusive! I even explained WHY! Twice, I tried to talk about it but she ignored me. I got home, looked it up in PubMed and people with DRD often respond to Artane. DUH!