In detail, a combination of two “severe” TMPRSS3 mutations with null protease activity in a trans configuration leads to profound deafness with prelingual onset (DFNB10), while the severe mutation—in combination with milder TMPRSS3 mutations with a significant residual protease activity—leads to a milder phenotype with postlingual onset (DFNB8) [8]. This evidence concerns the gene TMPRSS3 and deafness.