The SLC6 family of proteins, which includes SLC6A18, act as specific transporters for neurotransmitters, amino acids, and osmolytes like betaine, taurine, and creatine. SLC6 proteins are sodium cotransporters that derive the energy for solute transport from the electrochemical gradient for sodium ions (Hoglund et al., 2005 [PubMed 16125675]).[supplied by OMIM, Apr 2010].