From Science Alert:
Your risk for health issues including drug addiction and psychiatric disorders could in part depend on the genetic makeup of our childhood and adolescent social circles, according to a new study.
Researchers from Rutgers University in New Jersey looked at more than 650,000 Swedish health registry records for data on individuals aged 17 to 30 and their extended families, mapping risks for substance abuse and mental health problems. From this they determined their family genetic risk scores – the likelihood that their addiction or mood disorders had inherited features. Here’s what they found: if you’re hanging around with people who have a higher genetic risk of a variety of certain health problems, you’re more likely to develop them yourself, even if you don’t have the same risk mapped out in your own genes.