Novel CHM mutations in Polish patients with choroideremia – an orphan disease with close perspective of treatment

Anna Skorczyk-WernerEmail author View ORCID ID profile,
Anna Wawrocka,
Natalia Kochalska and
Maciej Robert Krawczynski

Orphanet Journal of Rare Diseases201813:221

https://doi.org/10.1186/s13023-018-0965-5

Received: 26 July 2018
Accepted: 27 November 2018
Published: 12 December 2018

Abstract

Background

Choroideremia (CHM) is a rare X-linked recessive retinal dystrophy characterized by progressive chorioretinal degeneration in the males affected. The symptoms include night blindness in childhood, progressive peripheral vision loss and total blindness in the late stages. The disease is caused by mutations in the CHM gene encoding Rab Escort Protein 1 (REP-1). The aim of the study was to identify the molecular basis of choroideremia in five families of Polish origin.

Methods

Six male patients from five unrelated families of Polish ethnicity, who were clinically diagnosed with choroideremia, were examined in this study. An ophthalmologic examination performed in all the probands included: best-corrected visual acuity, slit-lamp examination, funduscopy, fluorescein angiography and perimetry. The entire coding region encompassing 15 exons and the flanking intronic sequences of the CHM gene were amplified with PCR and directly sequenced in all the patients.

Results

Five variants in the CHM gene were identified in the five families examined. Two of the variants were new: c.1175dupT and c.83C > G, while three had been previously reported.