We report the isolation of cDNA clones for the mouse alpha 7 neuronal nicotinic acetylcholine receptor subunit (gene symbol Acra7), the only nicotinic receptor subunit known to bind alpha-bungarotoxin in mammalian brain. This gene may have relevance to nicotine sensitivity and to some electrophysiologic findings in schizophrenia. The mouse alpha 7 subunit gene encodes a protein of 502 amino acids with substantial identity to the rat (99.6%), human (92.8%), and chicken (87.5%) amino acid sequences. The alpha 7 gene was mapped to mouse chromosome 7 near the p locus with the following gene order from proximal to distal: Myod1-3.5 +/- 1.7 cM-Gas2-0.9 cM +/- 0.9 cM-D7Mit70-1.8 +/- 1.2 cM-Acra7-4.4 +/- 1.0 cM-Hras1-ps1/Igf1r/Snrp2a. The human gene was confirmed to map to the homologous region of human chromosome 15q13-q14.