More than 24,000 children are born with hearing loss in the United States each year. Boys Town National Research Hospital is a national leader in the diagnosis and treatment of children with moderate to profound hearing loss.

Information on Hearing Loss - Waardenburg Syndrome

A Dutch eye doctor, P. J. Waardenburg, was the first to notice that some people with two different colored eyes frequently had hearing problems. Dr. Waardenburg went on to study other chraacteristics of the syndrome which is now named after him.

The Waardenburg syndrome (WS) gene affects the body in three primary ways: hearing , pigmentation (coloring) of the skin, hair and eyes, and facial structure. Hearing. There is a great deal of variation in the sensorineural hearing loss among people with WS. At least half of those with the gene have no hearing problems. Only about one out of five have a hearing loss severe enough to require some aid to verbal communication. Some with the gene are totally deaf, and others are deaf in one ear, yet have completely normal hearing in the other ear.

Pigmentation

One of the noticeable effects is two different colored eyes (heterochromia irides). Usually, one eye is brown and the other is blue. occassionally, patches of brown and blue are mixed in the same eye. The blue eye color is often described as a "bright" blue. As with hearing loss, not everyone who carries the gene has two different colored eyes. in fact, in some large families with WS there may be only one or two such individuals. However, a person having two different colored eyes is so noteworthy that it almost always automatically raises the question of WS in that family.

In addition to the distinctive eye coloring, those with the WS gene may also have a distinctive coloring of the hair (poliosis). more frequently. one sees a white forelock, a patch of white hair starting at the front of the head and extending backwards. in addition, gene carriers become gray prematurely (in their twenties of thirties). Again, not all gene carriers have these distinctive markings. Also, premature graying of the hair and white forelock are common enough in the population that when they do occur, you cannot necessarily presume that the WS gene is present in the family.

Facial Structure

People with WS have a certain kind of look noticeable to the trained eye, but not so unusual that it is noted by the average person. The main feature is that the eyes appear to be more widely spaced than average. Usually, the eyes are not more widely spaced, but only appear so because the part of the face between the eyes is broader. If you have been to a geneticist who suspected WS, he or she probably measured the distance between your eyes to aid in the diagnosis. Synophris, or eye brows that grow together in the center, are sometimes a feature also. In addition to the three primary feature, there also can be cleft lip and or cleft palate or a colon problem (Hirschprung disease) in some individuals with WS. These last two features are even less common than the primary features. Other than the hearing loss, most people with WS do not have any particular medical problems. The facial feature and the pigmentary changes just help in making the diagnosis and cannot be considered abnormal. In fact these feature, especially the bright blue eyes are quite pretty.

Since WS is inherited in a dominant fashion, we typically see families with several generations of family members who have one or more of the features. Many of these family members are unaware that they have the gene because the feature can be so mild. In fact some individuals with the gene may not have any of the feature that we can detect. The chance of passing on the gene to their children is 50% regardless of the features they possess. of course, someone in a WS family who does not have the gene, cannot pass it on.

WS may be much more common in our population than previously believed. As many as two to three out of every hundred children in the schools for the deaf may have WS. Since the majority of those with the gene have little or no hearing loss, we believe that for every child we see with WS and a severe hearing loss, there are four to five family members who have relatively normal hearing but also have the gene.

There are mice that are called splotch mice because they have splotchy coloring in their coats. Scientists suspected that the gene that cause the splotchy coloring in the mice might the same gene that causes WS in humans. Since mice are easier to study, they were able to identify the gene that causes splotch in the mouse first. They then studied humans and found that there is the same gene in humans and it causes WS. The gene is named pax3 and is on human chromosome 2. With a mouse "model" to study, scientists are learning much about how the pax3 gene causes WS.

Date Originally Created: Fall of 1987 and updated in the Winter of 1996

The information presented here first appeared in publications of the Boys Town National Research Register for Hereditary Hearing Loss, the National Institute on Deafness and Other Communication Disorders (NIDCD), Hereditary Hearing Impairment Resource Registry (HHIRR), or the Boys Town Research Registry for Hereditary Hearing Loss.

The Boys Town Research Registry for Hereditary Hearing Loss

The Boys Town Research Registry for Hereditary Hearing Loss (Registry) is designed to foster a partnership between families, clinicians and researchers in the area of hereditary hearing loss/deafness through three primary functions. First, the Registry disseminates information to professionals and families about clinical and research issues related to hereditary deafness/hearing loss. Second, the Registry collects information from individuals interested in supporting and participating in research projects. This information is used to support the third function of the Registry - matching families with collaborating research projects.

For more information, contact us at:

Research Registry for Hereditary Hearing Loss
555 N. 30th Street Omaha, NE 68131
800 320-1171 (V/TDD)
402 498-6331 (FAX)