> The analysis done by Kong and his student relies on the key idea that a genetic sequence that occurs more frequently in participants than in nonparticipants will also occur more frequently in the genetic regions that are shared by two related participants.
> Put differently, a bit of DNA that is common in the population will show up frequently in the study. But it will still only have a 50/50 chance of showing up in the child of someone who carried a copy. If a bit of DNA makes people more likely to enroll in genetic studies, it will be more common both in the overall data and among closely related family members.
> So they checked the genetic sequences shared between first-degree relatives—either parents and children or siblings (but not twins)—in the UK Biobank.
Ok I guess that explains it. Still not following too well. If it's more common thatn 50/50 in children in the study of parents in the study, then it's probably involved in making 'genetic study' a predisposition?
Still pretty thin, maybe. Could be intelligence, or outgoing nature, or adaptability. Not some mysterious 'genetic study' gene.
Yes, no one's saying that people evolved a predisposition for participating in genetic studies specifically. It'll be some other traits like you suggested. The research is just saying "these databases are not randomly selected and we can prove it using only the database content". This is useful info to keep in mind when using the databases to draw conclusions.
I'd be more concerned if other studies didn't have the same genes. That is, is there something special about genetic study volunteers. If not, then we can remove the 'genetic' word from the title. I.e. "People in {any study} database have...'
> The analysis done by Kong and his student relies on the key idea that a genetic sequence that occurs more frequently in participants than in nonparticipants will also occur more frequently in the genetic regions that are shared by two related participants.
> Put differently, a bit of DNA that is common in the population will show up frequently in the study. But it will still only have a 50/50 chance of showing up in the child of someone who carried a copy. If a bit of DNA makes people more likely to enroll in genetic studies, it will be more common both in the overall data and among closely related family members.
> So they checked the genetic sequences shared between first-degree relatives—either parents and children or siblings (but not twins)—in the UK Biobank.