Symposium on sensorineural hearing loss in children: early detection and intervention. Genetic factors in deafness of early life.

One half of all cases of childhood deafness are genetically caused, and this proportion will become increasingly larger as other causes come under control. The mode of transmission of hereditary hearing loss may be dominant, recessive, or X linked. Many varieties of childhood deafness can be distinguished by their accompanying anomalies. Other types of hereditary deafness occur, without associated abnormalities. Certain of these types may be delineated by the mode of transmission, age of onset, stability or progression, and audiometric findings. Further research on delineation of nonsyndromic hearing loss in necessary if treatment of specific kinds is to become a reality. Research also is needed to detect the carrier state in recessive and X linked types of hearing loss. In the absence of means of prevention and treatment for most cases of hereditary deafness, genetic counseling remains the most valuable course.