Molecular basis of choroideremia (CHM): Mutations involving the rab escort protein-1 (REP-1) gene

Choroideremia: Effect of age on visual acuity in patients and female carriers

“…1 The incidence of CHM is estimated to be 1 in 100,000. 2 The responsible gene is located on Xq13-q22. In 1990, Cremers cloned the gene and in 1997 van Bokhoven isolated the complete coding sequences of this gene.…”

Clinical utility gene card for: Choroideremia

“…Deletions vary in size from a few kilobases removing a single exon to B15 Mb comprising the entire CHM gene and large parts of chromosome Xq21. 1 Two missense mutations have been reported: using in silico analysis, the c.1679 T4C (p.L550P) mutation was predicted to destabilise the b-structural elements and tertiary structure resulting in absence of REP1 in patient lymphocytes; 2 the c.1520A4G (p.H507R) missense was found to generate a functionally inactive REP1 variant that was not capable of interacting with RGGTase. 3 Carrier females are generally asymptomatic but funduscopic examination often shows patchy areas of chorioretinal atrophy that represent clonal areas of the disease due to random X-inactivation.…”

Lyonization in ophthalmology

“…The incidence of CHM is estimated to be 1 in 100 000 [18]. The gene underlying choroideremia was first described in 1990 [19,20] as the CHM gene at Xq21.2, encoding Rab escort protein 1 (REP-1) [19].…”