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All you should know about Waardenburg syndrome

Waardenburg syndrome refers to several rare genetic diseases that cause hearing loss, changes in the color of the eyes, skin, and hair, and changes in the shape of the face.

Researchers have identified four distinct types of the syndrome, though there may be additional subtypes.

Waardenburg syndrome is named after D. J. Waardenburg, a Dutch ophthalmologist who first identified the condition in 1951.

Fast facts on Waardenburg syndrome:

  • It is characterized by hearing loss and unusual color patterns in the eyes, skin, and hair.
  • A number of literary and television characters have had Waardenburg syndrome.
  • Waardenburg syndrome is a genetic disorder.

What is Waardenburg syndrome?

Waardenburg syndrome.
Those with Waardenburg syndrome may have a broad nasal root, causing the appearance of wide-set eyes.

It is common for people with this disorder to have eyes with spots or different colored eyes.

People with Waardenburg syndrome may also have an unusual facial shape and other changes in their appearance, such as prematurely gray hair.

Waardenburg syndrome is a congenital disorder, which means it is present from birth. There is no cure for the condition, but it can be managed.

What are the types of Waardenburg syndrome?

Doctors have identified four types of Waardenburg syndrome. Their symptoms vary, but people with each type tend to have similar symptoms. Types 1 and 2 are the most common.

Type 1

Type 1 Waardenburg syndrome causes someone to have a wide space between their eyes. About 20 percent of people with type I experience hearing loss. They also have patches of color or lost color on the hair, skin, and eyes.

Type 2

Hearing loss is more common in type 2 than type 1, with about 50 percent of people losing their hearing. The symptoms are otherwise similar to type 1, including changes in the pigment of the hair, skin, and eyes. This version of the disease is distinguished from type 1 primarily by an absence of a large space between the eyes.

Type 3

Type 3 is similar to types 1 and 2, frequently producing hearing loss and pigment changes. People with this form typically have a wide space between their eyes and a broad nose. The characteristic feature of type 3 that distinguishes it from types 1 and 2 is issues with the upper limbs.

People with type 3 may have weak arms or shoulders or malformations in their joints. Some also have intellectual disabilities or a cleft palate. Type 3 is sometimes called Klein-Waardenburg syndrome.

Type 4

Type 4 causes changes in pigmentation and may result in hearing loss. Additionally, people with this form have a disease called Hirschsprung disease. This disorder can block the colon, causing severe constipation.

Symptoms of Waardenburg syndrome

Bright blue eye with different colours.
Those with Waardenburg syndrome may have changes in their iris color, light skin, and early graying of hair.

The symptoms of Waardenburg syndrome vary depending on the type. Across types, most people have:

  • changes in vision
  • changes in color of the irises, each one often being different or having spots
  • early graying of the hair before 30 years of age
  • light-colored skin patches

Most people with Waardenburg syndrome have normal hearing, but hearing loss can occur across all four types.

Some people with Waardenburg syndrome experience other abnormalities, primarily affecting the shape of various body parts. Some of the most common ones include:

  • difficulties with tear production
  • a small colon
  • an abnormally shaped uterus
  • a cleft palate
  • partially albino skin
  • white eyelashes or eyebrows
  • a wide nose
  • a unibrow or single, continuous eyebrow

Symptoms vary substantially within types, but Type 3 tends to be the most debilitating. In addition to the typical symptoms of Waardenburg syndrome, people with type 3 may experience:

  • finger bones that are fused together
  • abnormalities in the arms, hands, or shoulders
  • microcephaly or an unusually small head
  • developmental delays or intellectual disabilities
  • changes in the shape of the bones of the skull

Causes of Waardenburg syndrome

The syndrome of diseases is not contagious, cannot be treated with medications, and cannot be caused by lifestyle or developmental factors.

Mutations in at least six genes are linked to Waardenburg syndrome. These genes help the body form various cells, especially melanocytes. Melanocytes are the cells that help give the skin, hair, and eyes their pigment.

Some genes involved in Waardenburg syndrome, including SOX10, EDN3, and EDNRB, also affect the development of nerves in the colon. The specific mutation a person has will determine the type of Waardenburg syndrome they develop.

Genetic causes of each type

Types 1 and 3 follow an autosomal dominant pattern of inheritance. Autosomes are chromosomes that are not sex chromosomes.

Dominant means that a person only needs to inherit one copy of a gene mutation to develop the disease. Most people with type 1 or 3 have a parent with the disorder.

Types 2 and 4 also follow a dominant inheritance pattern, but can also be inherited according to a recessive genetic pattern. This pattern requires two copies of a gene mutation and makes inheritance less likely.

Both inheritance patterns mean that a person is more likely to have Waardenburg syndrome if a parent or other close relative, such as a grandparent, has the disorder.

Recessive genes can hide for several generations, however, so not all people with Waardenburg syndrome have a living family member with the disorder.

How rare is Waardenburg syndrome?

Waardenburg syndrome is a rare disease, affecting about 1 in 40,000 people. Around 2 to 5 percent of all cases of deafness caused by gene abnormalities are the result of the syndrome. Though rare, Waardenburg syndrome may be common in a family because it is genetic.

Diagnosing Waardenburg syndrome

Doctors may suspect Waardenburg syndrome in a newborn baby based on the child s appearance. Doctors may also test babies for Waardenburg syndrome if they develop a hearing loss.

Most cases of Waardenburg syndrome are diagnosed in early childhood or infancy, though some cases can go undetected for many years.

Tests

Blood sample being used for DNA testing,
Waardenburg syndrome may be diagnosed by testing a DNA sample.

Testing requires a DNA sample, which is extracted from a person s blood. A lab can screen the DNA for genetic mutations linked to Waardenburg syndrome.

It is also possible to screen for genetic mutations associated with Waardenburg when a woman is pregnant.

How severe the symptoms of Waardenburg syndrome will be cannot be determined by these screening tests.

Treating and managing Waardenburg syndrome

People with Waardenburg syndrome have a typical life expectancy, and they can lead normal lives. There is no evidence that lifestyle or other environmental changes will affect their symptoms. Instead, treatment requires the management of the symptoms as they appear.

The most common treatments for Waardenburg syndrome include:

  • cochlear implants or a hearing aid to treat hearing loss
  • developmental support, such as special schools, for children with severe hearing loss
  • surgery to prevent or remove blockages in the intestines
  • a colostomy bag or other device to support intestinal health for bowel blockages
  • surgery to correct a cleft palate or cleft lip
  • cosmetic changes, such as dying the hair or using makeup to cover unusual skin pigment

A person with Waardenburg syndrome may need support to manage their condition, particularly if it affects their appearance in ways that are not easily changed. Support groups, family counseling, and education about the disease can help.

Takeaway

Waardenburg syndrome includes a wide variety of symptoms. Some people experience only minor changes in their appearance. Others face numerous functional challenges. There is no way to predict how Waardenburg syndrome will manifest or change over time in a given person.

However, knowing the type of Waardenburg syndrome a person has can help doctors plan appropriate treatment. With support and quality care, people with Waardenburg syndrome can lead long and healthy lives.