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"Noise-induced hearing loss (NIHL) is a common form of hearing loss and a growing health concern despite national standards for hearing protection and public health awareness campaigns. An NIHL gene association study with college-aged musicians has associated a non-synonymous single nucleotide polymorphism (rs61742642; C→T, P386S) in the ligand-binding domain of human estrogen-related receptor beta (ESRRβ) with increased susceptibility to bilateral 4 to 6 kHz hearing loss. ESRRβ protein is expressed in major cochlear structures except hair cells and tectorial membrane. ESRRB controls epithelial cell fate and endolymph production in the stria vascularis by regulating genes responsible for potassium ion transportation. Mutation in ESRRβ gene is associated with autosomal-recessive nonsyndromic profound hearing loss. The purpose of the study was to examine the effects of the ESRRβ polymorphism on temporary NIHL in young individuals. Methods: 19 individuals with rs61742642 CT genotype and 40 individuals with rs61742642 CC genotype were recruited for the study. Temporary NIHL was induced by 10 minutes exposure to 90 dB SL 2 kHz audiometric narrow-band noise and cochlear physiology was evaluated by a battery of clinical tests consisting audiometry, distortion product of otoacoustic emission (DPOAE) and transient evoked otoacoustic emissions (TEOAE). Input-output function of distortion product of OAE (DPOAE) was collected before and after the noise exposure using L1 = (0.40) L2 +39 at 2, 3 and 4 kHz. TEOAEs were collected using ILO quickscreen protocol with 84 dB peSLP with and without 50 dB SL contralateral broadband noise. Audiometric temporary threshold shift (ATTS), DPOAE temporary level shift (DPTLS), TEOAE temporary level shift (TETLS), TEOAE temporary level shift (TETLS) and TEOAE temporary suppression shift (TETSS) were evaluated to explore physiological basis of NIHL susceptibility related with the ESRRβ polymorphism. Results: A multiple regression analysis showed that individuals with rs61742642 CT genotype showed greater ATTS (β= 10.498 dB, CI = 6.413 - 14.583, p <0.001) without convincing evidence of change in DPTLS (β = -0.037 dB, CI = -0.663 - 0.589, p = 0.906), TETLS (β = -0.467 dB, CI = -1.573 - 0.640, p = 0.401) and TETSS (β = 0.224 dB, CI = -0.111 - 0.559, p = 0.186) compared with individuals with rs61742642 CC genotype. Individuals with the CT genotype showed poorer pre-exposure audiometric thresholds from 3 to 6 kHz in both ears with compromised DPOAE amplitude (β = -1.409 dB, CI = -2.662 - -0.156, p = 0.028) and TEOAE signal-to-noise ratio (F(1, 53) = 5.23, p = 0.026) in left ear. TEOAE 1/3 octave signal-to-noise ratios were higher (F(1, 53) = 5.037, p = 0.029) for females compared to males. Conclusion: The results indicate that individuals with the CT genotype are likely to get greater amount of metabolic compromise in cochlear physiology compared with individuals carrying CC genotype. The study associated the rs61742642 CT genotype with compromised pre-exposure poorer audiometric thresholds, reduced DPOAE amplitude and compromised TEOAE signal-to-noise ratio compared to individuals with CC genotype. The study suggests that the ESRRβ polymorphism is associated with increased susceptibility to NIHL, and also indicates the efficacy of otoacoustic emissions testing for identifying sound processing endophenotypes."--Abstract from author supplied metadata.