NRG1 and schizophrenia: While a number of studies demonstrated 50–80% of patients with schizophrenia have impaired SPEM compared to 8% of healthy individuals (Lencer et al., 2003; Ettinger et al., 2004), few studies have investigated genetic association of eye movement deficits with NRG1. A study of NRG1 genotypes with eye movement deficits in 113 patients with schizophrenia and 106 age-matched healthy controls found no relationship between NRG1 genotype (SNP8NRG222662, SNP8NRG243177) and ASEM or SPEM task performance (Haraldsson et al., 2010).