The recently described EPAS1 gain-of-function mutation syndrome (Pacak-Zhuang syndrome) is characterized by a constellation of multiple paragangliomas and pheochromocytomas, duodenal somatostatinoma, and polycythemia caused by postzygotic gain-of-function mutations in the EPAS1 gene, encoding for hypoxia-inducible factor 2α (HIF-2α). Because development of ocular structures requires proper coordination of hypoxia signaling, researchers evaluated patients with the syndrome for eye abnormalities and developed and evaluated a transgenic mouse model with a somatic heterozygous Epas1A529V mutation (corresponding to the human EPAS1A530V mutation) to establish the role of HIF-2α in the development of eye pathologies identified in the patients. This video of time-lapse fluorescein angiography demonstrates a venous plexus out towards the periphery of the eye with plexiform arteriovenous shunting (arrow) in a mutant mouse, mimicking some of the findings seen in humans. This and other findings from the mouse model suggests that HIF-2α is a critical component of the development of choroid and retinal vasculature and that abnormal vascular patterns in patients are developmental in origin. Click the related article for full details and discussion.
JN Learning™ is the home for CME and MOC from the JAMA Network. Search by specialty or US state and earn AMA PRA Category 1 Credit(s)™ from articles, audio, Clinical Challenges and more. Learn more about CME/MOC
You currently have no searches saved.
You currently have no courses saved.