Zellweger Syndrome

From WikiGenetics

1 Name of Condition
2 Definition
3 Description, Signs and Symptoms
4 Inheritance
5 Demographics
6 Diagnosis
7 Treatment and Management
8 Prognosis
9 Resources
10 References

[edit] Name of Condition

Zellweger Syndome, one form of a peroxisome biogenesis disorder (PBD).

[edit] Definition

Zellweger syndrome is an inherited condition that damages parts of the brain and affects metabolism. After birth, defects in the genes reduce or eliminate the presence of peroxisomes – cell structures that break down toxic substances in the cells of the liver, kidneys, and brain. As a result, high levels of iron and copper build up in blood and tissue and cause the characteristic symptoms of the disease.

[edit] Description, Signs and Symptoms

Symptoms of Zellweger Syndrome include an enlarged liver; facial deformities such as a high forehead, underdeveloped eyebrow ridges, and deformed ear lobes; and neurological abnormalities, such as mental retardation and seizures. Infants also lack muscle tone, sometimes to the point of being unable to move, and may not be able to suck or swallow. Some babies will be born with glaucoma, retinal degeneration, and impaired hearing. Jaundice and gastrointestinal bleeding may also occur.

[edit] Inheritance

Zellweger syndrome is an autosomal recessive condition caused by mutations on the PXR1 gene on the 12th chromosome. Genetic screening for couples, especially if one or both individuals has family members who have had Zellweger Syndrome, could prove beneficial to weigh the risks of having children born with the condition.

[edit] Demographics

Zellweger Syndrome occurs in approximately 1 in every 100,000 births. It is a congenital condition and often causes death at a young age.

[edit] Diagnosis

The distinctive characteristics are indicative of Zellweger Syndrome, and would suggest a diagnosis. This disease also causes the buildup of very-long-chain fatty acids (VLCFA), which can be measured by doing a blood test, and would confirm the diagnosis.

[edit] Treatment and Management

There is no cure for Zellweger syndrome, nor is there a standard course of treatment. Since the metabolic and neurological abnormalities that cause the symptoms of Zellweger syndrome are caused during fetal development, treatments to correct these abnormalities after birth are limited. Most treatments are symptomatic and supportive.

[edit] Prognosis

Zellweger syndrome is the most severe form of the four PBD diseases, and usually causes death by age 6 months. Less severe forms have better prognoses but still cause relatively premature death.