SPECIAL ARTICLE   

Otorhinolaryngology 2022 March;72(1):40-5

DOI: 10.23736/S2724-6302.21.02347-X

Copyright © 2021 EDIZIONI MINERVA MEDICA

language: English

From the DNA double helix to the epigenetics of deafness

Alessandro MARTINI ¹, Flavia SORRENTINO ² ✉

¹ Padova University Research Center “I - APPROVE - International Auditory Processing Project in Venice”, Santi Giovanni e Paolo Hospital, Venice, Italy; ² Otolaryngology Section - Head and Neck Surgery, Department of Neuroscience DNS, University of Padua, Padua, Italy

The first 3D structure of the DNA double helix was published almost 70 years ago, but it took at least another 50 years before it was possible to obtain a “molecular” diagnosis of deafness. The last three decades have seen impressive discoveries in the field of molecular genetics, which are contributing substantially to current knowledge of the etiology and pathology of several forms of hearing impairment. Thousands of mutations located on hundreds of genes have been identified as causative factors of syndromic and non-syndromic hearing loss. To date, there have been reports of about 170 NSHL loci and 119 genes having a causative role, and more than 400 syndromes associated with hearing loss have been described. As information accumulates on genetic disorders, their consequences for the structures and mechanisms of the auditory periphery are becoming clearer. In fact, a noticeable by-product of genomics comes from studies on how genes control proteins (proteomics), their role in organizing cochlear structure, the maintenance and regulation of metabolic cycles, and homeostasis. Therapeutic strategies for inner ear repair can be divided into two main categories: 1) for protection, to promote cell survival after damage; and 2) for hair cell regeneration after the cells have died. Epigenetics has been defined as “the science of change.” Understanding epigenetic mechanisms has become a major focus for research on most biological systems. To give an example, epigenetics can shed a great deal of light on how ototoxic compounds and noise affect gene regulatory networks. Such research will give us a better understanding of the complex gene regulatory networks regulated in the inner ear, and epigenetic factors have recently emerged as important regulators of both inner ear development and hair cell regeneration.

KEY WORDS: Deafness; Epigenomics; Hearing loss; Ear, inner