Natural History Of Choroideremia (Night Study)

Choroideremia is the result of a genetic mutation in the X chromosome. This is why the disease affects men and women differently. Women have two X-chromosomes and so one can compensate for the other to some extent. Men however only have one X-chromosome and cannot compensate when it is defective. The main purpose of this study is to assess/measure how Choroideremia develops over a period of 12 months. This information will be used to understand how quickly Choroideremia progresses and help advance understanding of the ways that disease progress can be measured. Eligible participants must be 18 years and older, be male, have a clinical diagnosis of Choroideremia and be in good general health.