Choroideremia carriers maintain a normal electro-oculogram (EOG).

Purpose: To assess the functional integrity of the retinal pigment epithelium and outer retina in choroideremia (CHM) carriers with confirmed mutations in the REP-1 gene, by recording the EOG.

Methods: The visual function of 17 choroideremia carriers ages 25-61 was assessed by determining their Snellen visual acuity and by recording the Arden ratio of the EOG. The 15 exons of the CHM gene were PCR-amplified from DNA from each of the carriers and their sequences were compared to the normal sequence to identify mutations.