ARHGAP21 and deafness: From the outlier analysis, we identified 38 candidate genes that may contribute to overall hearing status (including one deafness gene, PKHD1L1) (Table 4), 18 genes linked to Metabolic hearing loss alone (including four deafness genes, DMD, DUOX2, CELSR1 and ELMO3) (S3 and S5 Tables), and 54 genes linked to Sensory hearing loss alone (including four deafness genes, ARHGAP21, LMO7, UBE3B and ADGRV1) (S3 Table).