Abstract: The invention described in this disclosure relates to a cloned cDNA encoding the dopamine transporter protein usually found in certain neural cells. The invention is further directed to the purified dopamine transporter protein and its use as a biosensor material and immunogen for the production of anti-DAT1 antibodies. The disclosure also discusses methods for use of the cDNA for diagnostic and treatment applications, and methods for use of permanent cell lines transformed with the dopamine transporter cDNA for pharmaceutical screening. The use of anti-DAT1 antibodies as a diagnostic tool is also addressed.