But what kind of gene might be involved in an overly friendly personality?

His smile and friendly personality made him popular among most of the kids.

However, due to his friendly personality, he is very popular at school.

Thome's friendly personality has been the subject of much attention.

She has a friendly personality and aims to be a hairdresser.

He has a friendly and healthy personality, and is an expert in all kind of sports.

He is a young aspiring author with a seemingly friendly personality.

Kunichika was described as having an open, friendly and sincere personality.

He has a friendly, carefree personality and is a heavy smoker.

He has a lot of friends because of his friendly personality.