Tlili et al. (2005) described a 6-generation consanguineous Tunisian family of 54 individuals of which 10 were affected by a profound congenital non-syndromic deafness. Audiometric tests showed loss of hearing greater than 70 dB for all frequencies tested in all affected individuals. All deaf individuals were otherwise healthy, with normal life spans and without dysmorphic or other abnormal findings, including vestibular defects, skeletal or craniofacial malformations, subcutaneous calcifications, or neural tube defects. This disease mapped in the family (DFNB66) to chromosome 6p22.3-p21.2. A maximum lod score of 5.36 at theta = 0.0 was obtained for a polymorphic microsatellite marker. Tlili et al. (2005) screened 3 candidate genes within the DFNB66 locus on 6p22.3-p21.2, COL11A2, BAK1, and TMHS (LHFPL5), but found no disease-causing mutation. Later, Bensaid et al. (2011) checked whether DFNB66 and DFNB67 are distinctive loci by analyzing the DFNB66 family of Tlili et al. (2005). In the DFNB66 family, sequencing showed absence of mutations in the untranslated regions and the predicted promoter sequence of LHFPL5. However, analysis of five microsatellites in the 6p21.31-22.3 region and screening of the LHFPL5 gene revealed a novel mutation (c.89dup) in one out of 129 unrelated Tunisian families with autosomal recessive non-syndromic hearing loss. Bensaid et al. (2011) suggested that two distinct genes are probably responsible for DFNB66 and DFNB67 hearing loss.