This study aimed to investigate genes and variants associated with adult-onset progressive hearing loss, a common and complex disease with a strong genetic component.Participants enrolled in an ongoing longitudinal study of age-related hearing loss at the <a href="https://web.musc.edu/">Medical University of South Carolina</a> (MUSC), dating from 1987. Pure tone thresholds at 0.25, 0.5, 1.0, 2.0, 3.0, 4.0, 6.0 and 8.0 kHz were obtained for each ear of each person, along with questionnaire responses concerning noise exposure history. Based on the audiometry, participants were classified into 5 groups as "Older-Normal", "Metabolic", "Sensory", "Unclassified" and "Unselected" by their hearing loss.Exome sequencing was carried out using the Agilent SureSelect X2 Target Enrichment System (version 5) and the Agilent SureSelect Human All Exon V5 kit, which included 5' and 3' UTRs. DNA was sheared using the <a href="https://www.covaris.com/s220-focused-ultrasonicator-500217">Covaris S220 focused ultrasonicator</a>. Libraries were sequenced on the Illumina HiSeq 2500. Variant loads per gene were calculated and compared between groups. Individual variants affecting hearing thresholds were also identified. Analyses were followed up in a second cohort. Several genes and variants were identified as novel candidates associated with both better and worse hearing. Data available through dbGaP include whole exome sequencing (WES) files and audiometric phenotyping.

Experimental and Clinical Studies of Presbycusis

Classifying Human Audiometric Phenotypes of Age-Related Hearing Loss from Animal Models

Accurate phenotypic classification and exome sequencing allow identification of novel genes and variants associated with adult-onset hearing loss