A novel mutation in the TMC1 gene causes non-syndromic hearing loss in a Moroccan family.

•Sensorineural hearing loss is the most prevalent human genetic sensory defect.•A novel TMC1 gene mutation is described.•Whole exome sequencing was suitable for identifying mutation in the proband.•TMC1 can be a contributor of hearing loss in the Moroccan population.

Autosomal recessive non-syndromic hearing loss (ARNSHL) is one of the most common genetic diseases in human and is subject to important genetic heterogeneity, rendering molecular diagnosis difficult. Whole-exome sequencing is thus a powerful strategy for this purpose. After excluding GJB2 mutation and other common mutations associated with hearing loss in Morocco, whole-exome sequencing was performed to study the genetic causes of one sibling with ARSHNL in a consanguineous Moroccan family. After filtering data and Sanger sequencing validation, one novel pathogenic homozygous mutation c.1810C > G (p.Arg604Gly) was identified in TMC1, a gene reported to cause deafness in various populations. Thus, we identified here the first mutation in the TMC1 gene in the Moroccan population causing non-syndromic hearing loss.