Familial exudative vitreoretinopathy is a hereditary disorder that can cause vision loss that worsens over time. This condition affects the retina, the specialized light-sensitive tissue that lines the back of the eye. In people with this disorder, blood vessels do not fully develop at the outer edges (periphery) of the retina, which reduces the blood supply to this tissue. This prolonged reduction in blood supply (chronic ischemia) causes continued damage to the retina and can lead to worsening of the condition.

Variants (also called mutations) in the FZD4, LRP5, and NDP genes cause most cases of familial exudative vitreoretinopathy. These genes provide instructions for making proteins that participate in a chemical signaling pathway that affects the way cells and tissues develop. In particular, the proteins produced from the FZD4, LRP5, and NDP genes appear to play critical roles in the specialization of retinal cells and the formation of blood vessels in the retina and the inner ear. The LRP5 protein also helps regulate bone formation.

The prevalence of familial exudative vitreoretinopathy is unknown. It is thought to be rare, although affected people with normal vision may never receive a diagnosis.

Familial exudative vitreoretinopathy has different inheritance patterns depending on the gene involved. Most commonly, the condition results from variants in the FZD4 or LRP5 gene and has an autosomal dominant pattern of inheritance. Autosomal dominant inheritance means one copy of the altered gene in each cell is sufficient to cause the disorder. Most people with autosomal dominant familial exudative vitreoretinopathy inherit the altered gene from a parent, although the parent may not have any signs or symptoms associated with this disorder.

Published Date: February 05, 2024
Published By: National Institutes of Health