Genetic testing within the early hearing detection and intervention (EHDI) process, combined with genetic counseling and genetic evaluation, may define the cause of hearing loss, facilitate case management, and contribute to habilitation decisions. One gene, called GJB2, accounts for up to 50% of non-syndromic sensorineural hearing loss. Our early experience with a prospective longitudinal study of the impact of GJB2 testing in the newborn/early infancy period (n = 9 babies,10 parents) suggests that parents perceive that there are benefits of genetic testing for hearing loss, and understand important concepts about genetics and hearing loss after genetic counseling. GJB2-related hearing loss was confirmed in 5 babies. Additional findings illuminate the complexity of genetic test results, the importance of genetic evaluation in all individuals with hearing loss, and the difficulty in detecting some forms of syndromic hearing loss in the newborn period. Our experience highlights the importance o f combining genetic testing with genetic counseling and genetic evaluation. Professionals should be sensitive to ethical, cultural, and social aspects of genetic testing. [ABSTRACT FROM AUTHOR]