Does choroideremia affect more than the eye?

Overview

Choroideremia is a rare inherited eye disorder that mostly affects males. It starts in childhood with night blindness, leading to loss of vision by around age 40.

Although choroideremia is known as an eye disorder, there is some recent evidence that it may actually affect the whole body. Blood tests in small study of 5 men found that there might be a problem with how the body processes fats.

An online survey also found that men with advanced sight loss due to choroideremia reported more diabetes, high cholesterol and high blood pressure, and more were on statins, than respondents who still had some useful vision. But these are problems that are more common in older people and you would expect those with poorer vision to be older given that choroideremia gets worse over time.

The genetic glitch that causes the condition affects a protein called REP1 that’s important for how the body uses fats. Another protein – REP2 – does a similar job to REP1.

The researchers think it’s possible that REP2 is compensating for the faulty protein in the rest of the body but that it might not be able to in the eye. There is a type of fat that’s especially important in the eye, but it prefers working with REP1.

In this project the team will compare a larger group of men with choroideremia to healthy volunteers. The aim is to find out how fats are processed in people with choroideremia. Results from the study could answer the question of whether choroideremia affects more than the eye, and could also point to new ways to monitor and treat the condition.