What is Williams syndrome?
Williams syndrome is a rare genetic disorder that affects a
child's growth, physical appearance, and cognitive development.
People who have Williams syndrome are missing genetic material
from chromosome 7, including the gene elastin. This gene's protein
product gives blood vessels the stretchiness and strength required
to withstand a lifetime of use. The elastin protein is made only
during embryonic development and childhood, when blood vessels are
formed. Because they lack the elastin protein, people with
Williams Syndrome have disorders of the circulatory system and
heart defects.
How do people get Williams syndrome?
A deletion is caused by a break in the DNA molecule that makes up
a chromosome. In most cases, the chromosome break occurs while the
sperm or egg cell (the male or female gamete) is developing. When
this gamete is fertilized, the child will develop Williams
syndrome. The parent, however, does not have the break in any
other cells of the body and does not have the syndrome. In fact,
the break is usually such a rare event that it is very unlikely to
happen again if the parent has another child.
It is possible for a child to inherit a broken chromosome from a
parent who also had the disorder. But this is rare because most
people with Williams syndrome do not have children.
What are the symptoms of Williams syndrome?
The most common symptoms of Williams syndrome are mental
retardation, heart defects, and unusual facial features (small
upturned nose, wide mouth, full lips, small chin, widely spaced
teeth).
Other symptoms include: low birth weight, failure to gain weight
appropriately, kidney abnormalities, and low muscle tone.
People with this syndrome also exhibit characteristic behaviors,
such as hypersensitivity to loud noises and an overly outgoing
personality.
How do doctors diagnose Williams syndrome?
Doctors can identify the syndrome by its distinctive physical
characteristics. They can confirm the diagnosis by using a special
technique called FISH (fluorescent in situ hybridization).
The chromosomal deletion that causes Williams Syndrome is so small
that it cannot be seen in a karyotype. The deletion can be
observed, however, with FISH. This technique allows DNA sequences
to be labeled with a fluorescent chemical (called a probe) that
lights up when exposed to ultraviolet (UV) light. The Williams
Syndrome deletion can be detected by labeling the elastin gene
with a fluorescent probe. The gene will light up under a UV light
only if it is present; a lack of signal indicates a deletion.
How is Williams syndrome treated?
There is no cure for Williams syndrome. Patients must be
continually monitored and treated for symptoms throughout their
lives.
Interesting facts about Williams syndrome
One out of every 10,000 babies is born with Williams syndrome.
Williams syndrome is considered a microdeletion syndrome because
the deletion is too small to be observed microscopically (less
than 5 million bases of DNA are deleted).
When deletions occur during the formation of the egg and sperm, it
is caused by unequal recombination during meiosis. Recombination
normally occurs between pairs of chromosomes during meiosis while
they are lined up at the metaphase plate. If the pairs of
chromosomes don't line up correctly, or if the chromosome breaks
aren't repaired properly, the structure of the chromosome can be
altered. Unequal recombination occurs more often than usual at
this location on chromosome 7, causing Williams syndrome. This is
likely due to some highly repetitive DNA sequence that flanks the
commonly deleted region.
Growing Stronger, Growing
Better
Global Health
Healthcare Provider
Williams Syndrome - treatment of Williams
Syndrome, Williams Syndrome types, Disease medicines, Williams Syndrome
symptoms, Williams Syndrome and Disease symptoms, Williams Syndrome symptoms
Disease and diagnosis, Symptoms and Solutions, Signs and Symptoms, type of
Williams Syndrome, cause common, common Williams Syndrome, Williams Syndrome
List, causes list, Infectious Williams Syndrome, Causes, Diseases , Types,
Prevention, Treatment and Facts, Williams Syndrome information, Williams
Syndrome: Definition, Williams Syndrome names, medical Williams Syndrome,
medical Williams Syndrome and disorders, cell Williams Syndrome, Williams
Syndrome Worldwide, Williams Syndrome Research, Williams Syndrome Control,
Williams Syndrome Center, Digestive Williams Syndrome Week, Information
about Williams Syndrome, causes of different Williams Syndrome, Williams
Syndrome Articles, Williams Syndrome and conditions, Health and Williams
Syndrome, Williams Syndrome Patients, Williams Syndrome and Sciences, causes
of alzheimer's Williams Syndrome, Williams Syndrome causes, alternative
medicine heart Williams Syndrome, body ailments, Williams Syndrome
medicines, medical antiques, type of blood Williams Syndrome