PHOX2B and schizophrenia: So far, only a few risk genes were shown to be shared between strabismus and schizophrenia: PMX2B or PHOX2B/ARIX (Toyota et al., 2004; Toyosima et al., 2011), and AHI1 (Torri et al., 2010; Min et al., 2017), although additional ones may exist.