In genetic HL, the consequences of a sequence variant depend on gene type and location, as demonstrated by the genotype-phenotype correlations observed in Usher syndrome.37 Connexin 26–related HL is rarely associated with vestibular impairment (24.4% [10] of patients with PVF and 0 with CBVL in the present study [Table 2]), which can be explained by the sequence variation affecting the synthesis of a protein that is not present in the vestibule but in the cochlea.38 The gene discussed is GJB2; the disease is Usher syndrome.