The ZnT3 protein, encoded by the SLC30A3 gene, is located mainly in the brain, and to date, the SLC30A3 polymorphism has not been linked to human metabolic diseases but has been linked to schizophrenia and Alzheimer’s disease (Rovelet-Lecrux et al., 2012; Perez-Becerril et al., 2014). The gene discussed is SLC30A3; the disease is schizophrenia.