Choroideremia is a rare hereditary disorder that results in progressive vision loss. Predominantly affecting males, this vision loss is caused by the degeneration of the choroid and the retina. The choroid is a layer of cells between the retina and the sclera (the white of the eye). This network of choroidal blood vessels provides oxygen and nutrients to the retina. Symptoms typically begin in childhood or the teens with night blindness. This progresses to tunnel vision and eventually blindness, twenty to thirty years after onset.

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