In the Chinese population, previous studies showed that the incidence of the GJB2 c.235delC mutation was low in sudden hearing loss patients (2.1%, 5/234) and had no significant difference from that of normal controls, suggesting that GJB2 c.235delC has no correlation with sudden hearing loss (Zhan et al., 2014). The gene discussed is GJB2; the disease is sudden sensorineural hearing loss.