LOXHD1-related DFNB77 hearing loss and deafness is a condition that leads to moderate to severe hearing loss, usually starting in childhood.
In some cases, the hearing loss can get worse over time, especially in higher frequencies, while some people might retain some hearing at lower frequencies. There are rare instances where individuals are born with hearing loss that stays the same and doesn’t worsen over time. The level of hearing loss can vary among affected individuals, even within the same family. The age at which it begins also varies. Usually, it starts after language has developed, but in some cases, it can happen before language skills have fully developed. Unlike some other hearing problems, DFNB77 doesn’t affect a person’s ability to move or balance.
There’s a potential link between DFNB77 and a condition called corneal dystrophy, which affects the eye covering, but this connection hasn’t been conclusively proven. People affected might need to see an eye specialist for evaluation.
Depending on how severe the hearing loss is, some individuals might find hearing aids helpful. For those born with very severe hearing loss or for those whose hearing loss becomes so bad that hearing aids aren’t enough, cochlear implants could be an option. These individuals might also benefit from enrolling in educational programs designed for people with hearing impairments.
LOXHD1-related DFNB77 hearing loss and deafness is caused by pathogenic (disease-causing) variants in the LOXHD1 gene and exhibits autosomal recessive inheritance. This means that both parents must be carriers to have a 25% chance to have a child with the condition. The risk of being a carrier is based on a person’s ancestry or ethnic background. For example, individuals of Ashkenazi Jewish descent have a 1 in 180 chance to be a carrier.
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Revised October 2023
