Genetic hearing screenings for newborns
March 15, 2013 College News - The Medical College of Wisconsin has received a one-year, $20,000 grant from the American Hearing Research Foundation to perform genetic hearing screening in newborn babies at Children’s Hospital of Wisconsin.
Christina L. Runge, PhD, Associate Professor of Otolaryngology and Communication Sciences and Physiology, is the primary investigator. The screening will look for the most common genetic markers known to cause hearing loss at birth or predispose children to permanent hearing loss from environmental factors. Dr. Runge and a collaborative team of researchers will conduct a pilot study to ensure the test can be performed, and results shared with parents, in a timely and meaningful way.
Congenital hearing loss affects approximately one in 1,000 babies born in the United States each year, and it is estimated that half of the cases are genetic. Currently, 97 percent of newborns are screened for hearing loss at the time of birth by measuring an infant's responses to sound stimuli.
However, these tests are only able to identify hearing loss present at the time of the screening, and they do not provide information about the cause of hearing loss. Several forms of hearing loss develop later in life, and children at risk for these kinds of inherited hearing loss are not routinely tested and identified before the hearing problems start. By developing an effective protocol to genetically test newborns for mutations known to contribute to hearing loss at birth or later in life, appropriate follow up procedures, interventions and therapies can be started earlier in children who are at risk.
“The genetic markers of hearing loss we test for cause progressive and profound hearing loss, some of which would not necessarily be caught by the newborn physiological hearing screening performed soon after birth,” said Dr. Runge. “By testing for these markers, we could have more information that would help us make the most appropriate treatment recommendations for the child. For example, we may identify children who might be candidates for cochlear implants. There is a relationship between the age of implantation and the ability to develop language skills; therefore, the earlier we can identify these children to get them involved in therapy and fully assess their treatment options, the better.”
The screening will look for the most common mutations linked to congenital hearing loss and those that predispose patients to permanent hearing loss from environmental causes, such as certain ototoxic medications (medications that damage hearing cells in the inner ear).
The ultimate goal is for the genetic hearing screening to become a standard part of newborn testing at hospitals throughout the United States.