Additional guidelines for PS3/BS3 application at reduced strength levels were given for three genes: COCH, GJB2, and SLC26A4. Given the heterogeneity in disease mechanism underlying the multiple types of hearing loss, each gene was associated with a unique set of approved functional assays (Table 1; see also Additional file 1 for a detailed discussion of biological context of assays). Here, GJB2 is linked to hearing loss disorder.