APA Dictionary of Psychology

a family of genes that encode the nicotinic acetylcholine receptor (nAChR) subunits, which respond to the neurotransmitter acetylcholine and to nicotine, enabling cation flow across cell membranes. Each CHRN gene encodes a distinct subunit of the nicotinic acetylcholine receptor; some of these subunits have been linked to the brain’s reward pathways involved in nicotine and alcohol use, as well as to an increased risk of lung cancer. For example, variants in the CHRNA5-CHRNA3-CHRNB4 gene cluster have been associated with nicotine dependence, and some research suggests that variants in CHRNA4 may increase the risk of binge drinking. Also called neuronal nicotinic receptor genes.