By correlating blood oxygen level-dependent (BOLD) signals in the prefrontal cortex from schizophrenia patients and controls during a working memory task and genotyping data from a genome wide single nucleotide polymorphism (SNP)-array, Potkin et al. (2009) found that the BOLD signal significantly correlated with the presence of two SNPs within the SLC12A2 gene. Here, SLC12A2 is linked to schizophrenia.