TCF4 and schizophrenia: In patients with schizophrenia and controls, single nucleotide polymorphisms (SNPs) in the genome‐wide significant [Schizophrenia Working Group of the Psychiatric Genomics Consortium, 2014] gene TCF4 were significantly associated with verbal fluency (again, the number of words produced; individual group comparisons) [Wirgenes et al., 2012].