Hearing impairment (HI) is the most common sensory defect in humans. About 1 child in 650 suffers from HI before speech acquisition. This prelingual deafness has a genetic cause in 60% of the cases and 70% of the cases with genetic cause are isolated or non-syndromic. In nearly all of these cases, the disorder is monogenic with more tendency to follow an autosomal recessive inheritance pattern (DFNB, 80% of the cases). Autosomal recessive prelingual deafness is known to be genetically highly heterogeneous.