is a rare genetic syndrome
in which affected children are predisposed to develop Wilms tumor
(a tumor of the kidneys
(absence of the colored part of the eye, the iris
anomalies, and mental Retardation
. The G
is sometimes instead given as "gonadoblastoma," since the genitourinary anomalies are tumors of the gonads (testes
A subset of WAGR syndrome patients shows severe childhood obesity; the acronym WAGRO (O for obesity) has been used to describe this category.
The condition results from a deletion on chromosome 11 resulting in the loss of several genes. As such, it is one of the best studied examples of a condition caused by loss of neighbouring (contiguous) genes.
WAGR complex, Wilms tumor-aniridia syndrome, aniridia-Wilms tumor syndrome.
Clinical features and diagnosis
Newborn children with WAGR syndrome are soon noted to have aniridia. The clinical suspicion for WAGR may be increased with the presence of other genital anomalies, though genitourinary anomalies are not always present, particularly in girls.
In older children, clinical diagnosis of the syndrome can be made when aniridia and one of the other features are present. It must be noted that while aniridia is rarely absent in WAGR syndrome, cases have been reported without it. Chromosomal analysis is necessary for definitive diagnosis. Other common eye defects include cataracts and ptosis. About 50% of patients develop Wilms' tumor.
WAGR syndrome is caused by a mutation on chromosome 11
in the 11p13 region. Specifically, several genes in this area are deleted, including the PAX6
ocular development gene and the Wilms' tumor gene (WT1). Abnormalities in WT1 may also cause genitourinary anomalies. Mutations in the PAX6 gene have recently been shown to not only cause ocular abnormalities, but also problems in the brain and pancreas.
The gene for brain-derived neurotrophic factor (BDNF), located on 11p14.1, has been proposed as a candidate gene for the obesity and excessive eating in a subset of WAGR patients. This strengthens the case for a role for BDNF in energy balance.
WAGR syndrome was first described by Miller et al