WAGR syndrome is a rare genetic disorder that causes four distinct symptoms. Learn more about the genetics, prevalence, prognosis, diagnosis and treatment for the disorder.
Signs and Symptoms
WAGR syndrome is a rare genetic disorder that affects both sexes equally. The syndrome causes a predisposition for several health conditions that gives the syndrome its name:
Wilm’s tumor: a tumor that forms in the kidneys and is the most common form of kidney cancer in children.
Aniridia: partial or complete absence of the iris, the colored part of the eye.
Genitourinary problems: more common in affected boys, with the most occurring problem being undescended testes. In girls it can appear as underdeveloped ovaries, sometimes referred to as streak gonads.
Retardation: sometimes in combination with ADHD or obsessive compulsive disorder.
A small subset of affected individuals also suffers from childhood-onset obesity. This is than referred to as WAGRO syndrome.
Genetics of WAGR Syndrome
The cause of WAGR syndrome, also known as 11P deletion syndrome, is the deletion of genetic material on the short (p) arm of the 11th chromosome. . The aforementioned signs and symptoms of this disorder are all caused by this deletion of multiple genes. Two genes that are consistently lost in people affected with the syndrome are known as PAX6 and WTI1 which are significant in early development. It is thought that the loss of these two genes are responsible for several characteristic symptoms of the syndrome:
- PAX6: the loss of this gene appears to be associated with the eye problems (aniridia) and may affect brain development.
- WTI1: the loss of this gene seems to be responsible for Wilm’s tumor and the genitourinary problems related to WAGR syndrome.
Currently, research is being performed to identify other deleted genes in people suffering from this disorder and how their loss can lead to other characteristics of the syndrome. In general, WAGR syndrome is a sporadic disorder, meaning that it is not passed from parent to child. It rather results from a random event during the development of reproductive cells, or in early fetal development.
Prevalence and Prognosis
WAGR syndrome is a very rare disorder of which there are few estimates. It is thought that roughly one-third of the people with aniridia suffer from the syndrome, while about 7 in every 1,000 cases of Wilm’s tumor may be attributed to WAGR.
The prognosis for people affected by the syndrome is quite good, although this largely depends on the severity of the symptoms.
Diagnosis and Treatment
WAGR symptoms can be noticed shortly after birth. If one of these is present, genetic testing can provide conclusive evidence. A karyotype is done to look for the deleted area on chromosome 11, while a FISH (fluorescent in situ hybridization) test may be used to identify the loss of specific genes.
At present, there is no cure for WAGR syndrome. The treatment is aimed at the specific symptoms. An important part in the treatment is a regular follow-up on the physical condition of the patient to ensure that the present symptoms are not causing other problems.