Use of SLC26A4 mutation testing for unilateral enlargement of the vestibular aqueduct.
OBJECTIVE
Approximately one-half of all subjects with unilateral or bilateral hearing loss with enlargement of the vestibular aqueduct (EVA) will have SLC26A4 gene mutations. The number (0, 1, or 2) of mutant alleles of SLC26A4 detected in an individual subject with EVA is each associated with a distinct combination of diagnostic and prognostic information as well as probability of recurrence of EVA in siblings.


OBJECTIVE
To evaluate the results of SLC26A4 mutation testing in subjects with unilateral EVA. (The study objective was formulated before data were collected.)


METHODS
Prospective cross-sectional study of cohort ascertained between 1998 and 2012.


METHODS
National Institutes of Health Clinical Center, a federal biomedical research facility.


METHODS
Twenty-four subjects (10 males, 14 females) with unilateral EVA, defined as a midpoint diameter greater than 1.5 mm, who were referred or self-referred to participate in a study about the clinical and molecular analysis of EVA. Twenty-one (87.5%) of 24 subjects were white. Mean age was 10.3 years (age range, 5-39 years).


METHODS
SLC26A4 mutation analysis.


METHODS
Audiometric results, the presence or absence of EVA, and the number of mutant alleles of SLC26A4.


RESULTS
Approximately 8.3% of the subjects with unilateral EVA had 2 mutant SLC26A4 alleles, 16.7% had 1 mutant allele, and 75.0% had 0 mutant alleles.


CONCLUSIONS
Unilateral EVA can be associated with all possible SLC26A4 genotype results. The distinct combination of prognoses and recurrence probability associated with each genotype supports the clinical use of testing for SLC26A4 mutations in subjects with unilateral EVA.
Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland.
Parna
P
Chattaraj
Fabian R
FR
Reimold
Julie A
JA
Muskett
Boris E
BE
Shmukler
Wade W
WW
Chien
Anne C
AC
Madeo
Shannon P
SP
Pryor
Christopher K
CK
Zalewski
John A
JA
Butman
Carmen C
CC
Brewer
Margaret A
MA
Kenna
Seth L
SL
Alper
Andrew J
AJ
Griffith
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004252:DNA Mutational Analysis; D005786:Gene Expression Regulation; D005820:Genetic Testing; D005838:Genotype; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics*; D006801:Humans; D006984:Hypertrophy / Q000235:genetics; D015994:Incidence; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics*; D009154:Mutation; D011379:Prognosis; D011446:Prospective Studies; D000076988:Sulfate Transporters; D014057:Tomography, X-Ray Computed / Q000379:methods; D014723:Vestibular Aqueduct / Q000473:pathology*; D055815:Young Adult
D026901:Membrane Transport Proteins; C085609:SLC26A4 protein, human; D000076988:Sulfate Transporters