Aniridia + deletion, FISH probes

Human chromosomes highlighted by fluorescent probes which bind to specific sequences of DNA. This FISH (fluorescence in situ hybridisation) study is of a patient with aniridia and a cytogenetically visible deletion in chromosome 11, 11p13p15.1. The chromosome 11 centromeres are shown in green. The upper cell shows that the deletion includes the aniridia gene (PAX6) (red) but does not include the Wilm's tumour predisposition gene WT1 (shown red in lower cell). This result suggests that this patient is at low risk for developing Wilm's tumour. Image by Dr John Crolla.