The Crucial Link For Sensory Development in The Ear

Editor: It seems that we are reporting new developments in the understanding and potential cure of hearing loss nearly every month. Here's a press release from Medical Research Council (MRC) and the University of Hong Kong that announces the isolation of the gene responsible for sensory development in the inner ear!

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Scientists from the Medical Research Council (MRC) and the University of Hong Kong have isolated the gene responsible for sensory development in the inner ear, which may lead to significant advances in the development of treatments for the deaf and severely hearing impaired, according to research published in the current issue of Nature.

i-Newswire, 2005-04-22 - The team made the discovery that the Sox2 gene was involved after studying two types of mice, one of which was completely deaf and the other had severe hearing impairment. Both also had balance problems. Knowing that sensory hair cells detect sounds and their associated supporting cells in the inner ear are fundamental for hearing, the researchers studied the gene activity of these cells in the ears of the two groups of mice.

Whilst the deaf mice in the study had no sensory hair cells and had severe inner ear malformation, the mice with severe hearing impairment showed abnormal development with disorganised and few sensory hair cells. Scientists found that these characteristics are due to the absence ( in the deaf mice ) and the reduced expression ( in the hearing impaired mice ) of the gene Sox2.

Professor Robin Lovell-Badge of the MRC's National Institute for Medical Research, says: "A number of genes have been found that are required to make functional hair cells, the cells that detect sound or movement and balance in the inner ear, but we didn't find genes that initiate development of the sensory system, which comprises both the hair cells and their supporting cells. So the discovery that the Sox2 gene does this is a significant step forward. To develop treatments for deafness in the future, it is now necessary to look at whether this gene can play a part in bringing damaged sensory hair cells back to life or in triggering new sensory cells to grow for use in potential stem cell therapy."

The Medical Research Council ( MRC ) is a national organisation funded by the UK tax-payer. Its business is medical research aimed at improving human health; everyone stands to benefit from the outputs. The research it supports and the scientists it trains meet the needs of the health services, the pharmaceutical and other health-related industries and the academic world. MRC has funded work which has led to some of the most significant discoveries and achievements in medicine in the UK. About half of the MRC's expenditure of £450 million is invested in its 40 Institutes, Units and Centres. The remaining half goes in the form of grant support and training awards to individuals and teams in universities and medical schools.

Web site at: http://www.mrc.ac.uk.