Rockefeller University is looking for families with a history of hearing impairment to participate in a study aimed at identifying the genetic causes of non-syndromic hearing loss (NSHL), which is hallmarked by hearing impairment without other simultaneously occurring medical conditions. This study is part of the research program of the University's Starr Center for Human Genetics.
"By focusing on families with a history of hearing loss, we are attempting to find genes that are involved in the process of hearing. This information could aid in the development of intervention strategies to treat and prevent hearing loss," says Suzanne Leal, Ph.D., principal investigator of the study and assistant professor in the Laboratory of Statistical Genetics at Rockefeller.
Hearing impairment, which ranges in severity from modest difficulty with speech comprehension through profound hearing loss, affects 28 million Americans. About two in every 1,000 children are severely hearing impaired before adulthood. More than 60 percent of the cases of profound early-onset deafness are caused by genetic factors, which in most cases are due to single gene mutations.
According to three U.S. studies conducted between 1991 and 1993, NSHL affects three out of four individuals with genetically determined deafness. Inheritance of NSHL can be in either of two forms: autosomal dominant, in which only one copy of the hearing loss gene is necessary, or autosomal recessive, in which two copies of the gene is needed. The latter of the two forms represents approximately 75 percent of all genetic hearing loss cases.
It has been estimated that as many as 100 genes may contribute to NSHL. The locations, or loci, for more than 30 genes have been found, but scientists have identified only seven genes thus far.
Therefore, the main goals of Leal's study are to localize novel NSHL gene(s),
establish the prevalence and geographical distribution of these loci, refine the
genetic region for
Contact: Paul C. Focazio