HCN1 and schizophrenia: Findings of a GWAS on a smaller sample including 726 patients with schizophrenia and 667 healthy controls suggested that variants in a few genes may modulate cognitive phenotypes: NRG3 (neuregulin 3) for abstraction and mental flexibility, SHANK3 (SH3 And Multiple Ankyrin Repeat Domains 3) and HCN1 (hyperpolarization activated cyclic nucleotide gated potassium channel 1) for spatial memory (Greenwood et al., 2019).