Neurotransmitter transport systems are major targets for therapeutic alterations in synaptic function. We ha ce cloned and sequenced a cDNA encoding the human type 2 glycine transporter GlyT2 from human brain and spinal cord. An open reading frame of 2391 nucleotides encodes a 797 amino acid protein that transports glycine in a Na+/Cl--dependent manner. When stably expressed in CHO cells, human GlyT2 displays a dose-dependent uptake of glycine with an apparent K-m of 108 mu M. This uptake is not affected by sarcosine at concentrations up to 1 mM. Radiation hybrid analysis mapped the GlyT2 gene to D11S1308 (LOD = 8.988) on human chromosome 11p15.1-15.2. (C) 1998 Federation of European Biochemical Societies.