GJB2 and deafness: (ii) In the subgroup with DFNB1-related deafness, functional MMP9 variant rs3918242 significantly impacts auditorydevelopment measured at the 18th month after the deviceactivation; it is also a significant predictor of overall LEAQ score in the subgroupwith DFNB1-related deafness and activation after at the 1 year.