The Twin Research Department hearing test collection was started in 2010 with a pure-tone audiogram performed during the twin visit at the department of Twin research. This test measures the lowest sound intensity an individual can hear at different frequencies. Every hearing test was also accompanied by a questionnaire covering environmental risk factors for hearing ability (i.e. self reported hearing loss; previous ear diseases and surgery; noise exposure) and a short examination of the outer ear. We have so far collected hearing tests from 1300 volunteers from the Twins UK cohort.
In 2011 we started recruitment for a novel hearing test that could be performed at home via the web. This test has been developed by Action on Hearing Loss and was kindly set up by them for the TwinsUK coho. 1900 twins have taken the challenge so far and checked their hearing via this novel tool. We compared both hearing tests to determine the sensitivity of the web based test to pick up hearing loss correctly as well as showing hearing ability to be heritable (Wolber et al. 2012).
In our research we look at environmental risk factors, genetic and epigenetic factors increasing your risk to develop presbycusis. We have shown that hearing ability at higher age is determined up to 70% by genetic factors, with environmental exposure explaining the remaining 30% of variation in hearing ability. Furthermore, we have compared genetic variations genome-wide for twins with good and bad hearing ability with age and can identify several genetic markers associated with hearing. Our results will be strengthened by our combining results with those of hearing consortium G_EAR. We have collaborations with genetic epidemiologists having hearing data and hearing geneticists with cell and animal models with whom we plan to take the results forward.
Dr Frances Williams
Wolber LE, Girotto G, Buniello A, Vuckovic D, Pirastu N, Lorente-Cánovas B, Rudan I, Hayward C, Polasek O, Ciullo M, Mangino M, Steves C, Concas MP, Cocca M, Spector TD, Gasparini P, Steel KP, Williams FM. Salt-inducible kinase 3, SIK3, is a new gene associated with hearing. Hum Mol Genet. 2014 Jul 24. pii: ddu346. [Epub ahead of print]
Wolber LE, Steves CJ, Tsai PC, Deloukas P, Spector TD, Bell JT, Williams FM. Epigenome-wide DNA methylation in hearing ability: new mechanisms for an old problem PLoS One. 2014 Sep 3;9(9):e105729. doi: 10.1371/journal.pone.0105729.