Next-Generation Sequencing-Based Molecular Diagnosis of Choroideremia

Abstract

We screened patients with choroideremia using next-generation sequencing (NGS) and identified a novel mutation and a known mutation in the CHM gene. One patient presented an atypical fundus appearance for choroideremia. Another patient presented macular hole retinal detachment in the left eye. The present case series shows the utility of NGS-based screening in patients with choroideremia. In addition, the presence of macular hole in 1 of the 2 patients, together with a previous report, indicated the susceptibility of patients with choroideremia to macular hole.

Keywords: Choroideremia; Diagnosis; Next-generation sequencing; Utility.

Fig. 1

Fundus photographs showing diffuse chorioretinal atrophy throughout the entire retina in both eyes (upper left). The visual field was severely impaired with only small islands remaining (lower left). Sanger sequence confirmed the 2-bp deletion (upper right, arrow). In addition, there was another single nucleotide polymorphism c.1722C>T, which was synonymous if without a frameshift. Family history suggested autosomal recessive or X-linked inheritance trait (middle right). OCT scan showing abnormal thinning of the retina in both eyes. MHRD was noted in the left eye (lower right).

Fig. 2

Fundus photographs showing chorioretinal atrophy, spreading from the posterior pole, except for macula area, to around the equatorial fundus (upper left). The visual field showed ring-shaped scotoma (lower left). Sanger sequencing confirmed the presence of the mutation (upper right). Family history suggested autosomal recessive inheritance trait (middle right). OCT showed loss of photoreceptors in both eyes. Foveal thickness was relatively preserved (lower right).