11p13

11p13 is a cytogenetic region on the short arm of chromosome 11. The band 11p13 encompasses several genes, including PAX6 and WT1, and deletions that span this region are associated with a contiguous gene syndrome known as WAGR syndrome when both genes are affected. The syndrome is named for its main features: Wilms tumor, Aniridia, Genitourinary anomalies, and developmental delay or intellectual impairment.

Genetics and presentation

Most 11p13 deletions arise de novo, but they can be inherited in an autosomal dominant pattern if a parent carries a deletion. The clinical phenotype varies with the size and boundaries of the deletion. Aniridia results from PAX6 haploinsufficiency, while the WT1 deletion confers an increased risk of Wilms tumor and other genitourinary anomalies. Additional features may include developmental delays, learning difficulties, and other congenital anomalies depending on the extent of the deletion and involvement of neighboring genes.

Diagnosis

11p13 deletions are detected primarily by chromosomal microarray analysis (array CGH) or fluorescence in situ hybridization (FISH) targeting 11p13. Conventional karyotyping may identify larger deletions. Prenatal testing is possible if a familial deletion is known or clinical concern exists.

Management and prognosis

Management focuses on early tumor surveillance for Wilms tumor, typically with regular abdominal ultrasound in early childhood, and ongoing monitoring for genitourinary anomalies. Ophthalmologic evaluation is essential for detecting and managing aniridia. Supportive care includes developmental assessments and educational interventions. Genetic counseling addresses recurrence risk, which depends on whether the deletion is de novo or inherited. With appropriate monitoring, outcomes can improve for affected individuals.