Novel Genetic Loci Identified for High-Frequency Hearing Loss

As people get older, they gradually lose the ability to hear high-pitched sounds. This occurrence is called presbycusis. The genetic loci have been recently found that affects a human’s ability to hear high pitched sounds. These genetic loci affect certain portions of the hearing frequency map and especially the loss of hearing as age increases. The National Institute of Deafness and other Communication Disorders (NIDCD) successfully identified two loci that affected hearing at high frequencies. These two loci are Hfhl1 and Hfhl3. To discover these two loci the NIDCD used genome-wide linkage analysis. The Hfhl1 loci is thought to be confined to hearing frequencies from 25-44 kHz of the tonotopic map. The Hfhl3 loci is thought to be confined to the 35-44 kHz region on the tonotopic map inside the inner ear. The loss of high-pitched sounds is a result of variations in gene activity and cochlear partition. There is different hearing sensitivity located in different sections of the cochlea of the inner ear. The loci Hfhl1 and Hfhl3 account for only a portion of the variation in high-pitched hearing loss. Additional genotyping and analysis needs to be done in order to find the remaining loci that affect high-pitched frequency loss.