Groundbreaking gene therapy restores hearing in deaf children

Source: The Good News Network

In China, a true medical breakthrough has been achieved in a human trial that had as many as 10 children born deaf have their hearing restored through a genetic therapy method.

MIT hailed it as China’s first domestic gene therapy breakthrough, as well as “the most dramatic restoration of a lost sense yet achieved.”

Much like other gene therapy treatments, children like Li Xincheng were injected with a reprogrammed virus that carried replacement DNA into the part of her body the scientists hoped to alter—in this case the location of the inner ear canal that detects vibrations and sends that information to the brain.

In less than a month, her mother, Qin Lixue, said she was hearing out of her treated ear for the first time in her 5 years of life, and repeating various rhymes and songs back to Lixue as she sang them with her hand over her mouth to prevent lip-reading.

It bears repeating that this, according to MIT Technological Review, has never happened before.

“We were careful, and a little bit nervous, because it was the first in the world,” says Yilai Shu, a surgeon and scientist at Fudan University in Shanghai, and part of the team who treated 5 children.

“Before the treatment, if you put them in a movie theater with the loudest sound, they wouldn’t hear it,” says Zheng-Yi Chen, an associate professor at Mass Eye and Ear, a Harvard-affiliated hospital in Boston, who helped design and plan the study. “Now they can hear close to normal speech, and one can hear a whisper.”

Of Shu’s five children, 4 recovered hearing, and one did not, which the team hypothesizes could be because the child already had a developed immune response to the virus that they used.

This new gene therapy is not a cure-all, as it was designed to correct a defect in a gene that produces a protein called otoferlin that is necessary to build the special hairs that vibrate to different frequencies in the inner ear and relay that information to the brain.

This is present in only 1% to 3% of those born deaf, amounting to 900 children a year in the world’s second-most populated country. But Lawrence Lustig, a physician at Columbia University who runs studies of hearing treatments, told MIT Tech Review that this dramatic success—allowing children to hear sound for the first time—may be a “gateway drug” that spurs funding toward more causes of deafness.

Genetic therapy, such as CRISPR and other methods, has also had remarkable successes with blindness, including in 2021 of a Frenchman with retinitis pigmentosa, the degradation of photoreceptive cells in their eyes, another two patients from Portland, Oregon who had Leber congenital amaurosis, or LCA, a rare mutation in the retina, and another 10 with LCA who were treated at the Perelman School of Medicine in the University of Pennsylvania.