Why do people use or get addicted to cannabis? A new study offers clues. The Washington PostGenes Linked to Cannabis Use Reveal Ties to Mental Health Neuroscience NewsCannabis Abuse Genetically Linked to Psychiatric Traits, Physical Health Inside Precision MedicineLarge Genetic Study Links Cannabis Use to Psychiatric, Cognitive and Physical Health UC San Diego TodayThe genetics of cannabis lifetime use - Neuropsychopharmacology Nature