To demonstrate the role of rs6994992 in schizophrenia, many studies have been conducted to investigate the association between NRG1 rs6994992 and schizophrenia in different ethnic populations (e.g., Stefansson et al., 2002, 2003; Zhao et al., 2004; Petryshen et al., 2005; Li et al., 2006). This evidence concerns the gene NRG1 and schizophrenia.