BOR syndrome associated with EYA1 mutations, together with other syndromic or genetic causes cochlear hypoplasia, exhibit an intermediate phenotype: where the basal turn shows again a normal first half, while the second half and the upper turns are moderately hypoplastic and anteriorly offset, though less prominently than in the WWS phenotype (Fig. 1B and C). Here, EYA1 is linked to BOR syndrome.