> How did they control it? Even amongst Europeans, I imagine French people are just more likely to have French friends. This study is in the US. By "people of

> How did they control it? Even amongst Europeans, I imagine French people are just more likely to have French friends. This study is in the US. By "people of european descent", they are referring to white americans rather than actual europeans. Also french is a linguist/national/ethnic classification rather than a genetic one.