Clinical and genetic study of a new mutation in the choroidoremia gene

Abstract

PurposeTo describe retinal findings as well as spectral domain OCT and fundus autofluorescence in a new genetic mutation in a choroidoremia family.MethodsAn 11 year old boy was diagnosed with choroidoremia by his fundus changes. In his mother′s family there was another cousin with the same symptoms and his grandfather and great grandfather had an impaired vision. The family was studied.ResultsThe boy has a reduced visual acuity of 20/40 in both eyes with ‐6D, reduced sensibility in his perimetry, and important retinal pigment changes in his fundus. SD‐OCT findings include changes in the external hyperreflective layers and hypofluorescence and hyperfluorescence changes in his fundus autofluorescence. His mother showed a normal OCT with hypofluorescence changes. His cousin, who was 13 years old, showed similar changes with a 20/20 vision and no myopic defect. The boys were hemizygous for a novel mutation c.1083_1084dupT of the CHM gene. The mutation was confirmed in heterozygosity in both carriers. The sister was not affected.ConclusionsClinical diagnosis and molecular analysis showed the new mutation leading to loss of function of the REP‐1 protein. Autofluorescence changes were presented in both patients and carriers. Myopia could increases the visual loss and pigment changes in choroidoremia.