The present invention relates to a polynucleotide encoding a human brain-derived G protein coupled receptor protein. The human brain-derived G protein coupled receptor protein is useful: (1) for determination of a ligand to the receptor protein, (2) as an agent for the prevention and/or treatment of diseases associated with dysfunction of the receptor protein, (3) as a genetic diagnostic agent, (4) for quantification of a ligand to the receptor protein, (5) for screening of a compound that alters the binding property between the receptor protein and a ligand, (6) as an agent for the prevention and/or treatment of various diseases, comprising a compound that alters the binding property between the receptor protein and a ligand, (7) for quantification of the receptor protein, (8) for neutralization by antibodies to the receptor protein and (9) for preparation of a non-human animal bearing the DNA encoding the receptor protein.