NEW ORLEANS (February 9, 2013)—In a promising step against a genetic disease that causes deafness and gradual loss of vision, scientists report that they have partly restored hearing with a single injection to young mice.

Experts praised the study on Usher syndrome, published online last week by the journal Nature Medicine, but the results are still a long way from finding a way to prevent the disease, which affects an estimated one in 6,000 to 7,500 babies worldwide.

Louisiana's Cajuns and other groups have an unusually high prevalence.

In the study, researchers found that one gene-inhibiting injection allowed affected mice to hear for months.

The researchers plan four more years of studies to learn the treatment's physical effects and to refine the timing of shots and boosters.