Scientists are one step closer to understanding the genetic pathway involved in the development of hearing. New research findings, published online in the journal Nature Genetics, detail how sensory hair cells in the ear - the cells largely responsible for hearing - develop unique shapes that enable the perception of sound.
Located in the spiraled cochlea, the hearing portion of the inner ear, the hair cells transform the mechanical vibrations that enter the ear in the form of sound waves into chemical signals, which they then direct to the brain. Ping Chen, PhD, assistant professor of cell biology at Emory University School of Medicine, and her colleagues found that the development of cochlea and hair cells is dependent on a genetic pathway called the PCP (planar cell polarity) pathway.
Although some species, including birds, are capable of re-growing hair cells, mammals lack the ability to naturally regenerate hair cells. Thus individuals born with improperly developed hair cells, or those who lose them through trauma, disease, environmental factors or aging, cannot regain their hearing. Reports from the National Institutes of Health (NIH) indicate that severe hearing impairment affects 28 million Americans. That number includes the approximately 4,000 Americans each year who suffer from sudden deafness, and the roughly 12,000 children born each year with difficulty hearing.