Sheffield, UK — A University of Sheffield research team led by Dr Walter Marcotti, Royal Society University Research Fellow, in collaboration with Professor Karen Steel at the Sanger Institute in Cambridge, has discovered that a mutation in the gene known as “miR-96” prevents development of the auditory sensory hair cells.

The research has been published in the January 2011 edition of the Proceedings of the National Academy of Sciences. The authors used studies of mice, which do not normally hear until about 12 days after birth. Prior to this age, their immature hair cells must execute a precise genetic program that regulates the development of distinct types of sensory hair cell, namely inner and outer hair cells.

The research teams found that in a strain of mice called diminuendo, which carry a single base mutation in the miR-96 gene, hair cell development is stopped around birth.

The researchers found that miR-96 normally regulates hair cell development and that the mutation hinders the development not only of the mechanically sensitive hair bundle on the cell apex, but also the synaptic structures at the base that govern transfer of electrical information to the sensory nerves. These new findings suggest that miR-96 is a master regulator responsible for coordinating the development of the sensory cells that are vital to hearing.

Since the mutation in miR-96 is known to cause human deafness and drugs can target microRNA molecules, the work also raises new opportunities for developing treatments to treat hearing loss.

SOURCE: University of Sheffield