Nicotinic Receptor Genetic Variation and Alcohol Reward

Background: People with the brain disease AUD (alcohol use disorder) have a serious problem with drinking. Researchers want to study how different people react to alcohol, and how genes affect this. They will focus on a nicotine receptor gene that may increase a person s AUD risk. Objectives: To see if people with variations of a nicotine receptor gene take alcohol differently and have different brain responses to alcohol cues. Eligibility: Healthy adults ages 21 - 60. This study includes smokers and non-smokers. Design: Participation will be based on evaluation under the NIAAA natural history protocol (14-AA-0181) or a screening visit under this protocol. Participants will have two 9-hour visits. They must have no alcohol or non-prescription drugs before all visits and no food or drink before the first visit. At every visit, participants will: * Get a light meal * Have breath and urine tests * Get taxi rides there and back At visits 1, participants will: * Have a thin plastic tube inserted in an arm and connected to a pump for alcohol infusion. * Have sensors on their chest to monitor heart rate. * Sit in a chair for 2.5 hours and get alcohol by pushing a button. Their breath alcohol level will be monitored. * Answer questions about mood and effects of alcohol * Give blood samples * Relax at the clinic while their breath alcohol level drops At visit 2, participants will: * Answer questions and do computer tests * Have an alcoholic drink and a snack * Have a magnetic resonance imaging (MRI) scan. They will lie in a machine that takes pictures of the brain. They will do computer tasks. * Have another drink and snack * Relax until their alcohol level drops Participants will have a follow-up call after each visit.