A Prospective Study of Genetic Variants in Infants with Congenital Unilateral Sensorineural Hearing Loss

Abstract

Children with unilateral sensorineural hearing loss (uSNHL) have a high risk of speech-language delays and academic difficulties. Still, challenges remain in the diagnosis of uSNHL. With a prospective cross-sectional design, 20 infants were consecutively recruited from a universal newborn hearing screening program and invited to genetic testing. Eighteen of the subjects agreed to genetic testing, 15 subjects with OtoSCOPE® v.9 screening 224 genes, and four subjects underwent targeted testing, screening for chromosomal abnormalities or 105–137 gene mutations. The genetic results were described together with the 20 infants’ previously published auditory profiles and imaging results. Genetic causes for the uSNHL were found in 28% of subjects (5/18) including CHARGE syndrome (CHD7), autosomal recessive non-syndromic hearing loss (GJB2), Townes–Brocks syndrome (SALL1), Pendred Syndrome (SLC26A4) and Chromosome 8P inverted duplication and deletion syndrome. In subjects with comorbidities (malformation of fingers, anus, brain, and heart), 100% were diagnosed with a genetic cause for uSNHL (3/3 subjects), while 13% (2/15 subjects) were diagnosed without comorbidities observed at birth (p = 0.002). Genetic testing for congenital uSNHL is currently efficient for alleged syndromes, whereas genetic variants for non-syndromic congenital uSNHL need further research.