Phenotype variations within a choroideremia family lacking the entire CHM gene.
A Swedish family with choroideremia and a deletion of the CHM gene has been studied with ophthalmological examination, full-field electroretinography, and DNA analysis in order to characterize the phenotype of the disease. Although all four patients studied had a complete deletion of the gene, they showed a considerable variability regarding the phenotype, including the electroretinogram tracings. Two of the affected males demonstrated a severe form of choroideremia with low or nondetectable ERG recordings, while the other two affected males showed a less severe phenotype with only a slight reduction of the ERG amplitudes. The variation of the clinical phenotype among family members carrying the same mutation indicates that the severity of choroideremia is not solely a function of the CHM gene.
Ponjavic
V
V
Department of Ophthalmology, University of Lund, Sweden.
Abrahamson
M
M
Andréasson
S
S
Van Bokhoven
H
H
Cremers
F P
FP
Ehinger
B
B
Fex
G
G
D000328:Adult; D000368:Aged; D002648:Child; D015794:Choroideremia / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology; D004252:DNA Mutational Analysis; D004591:Electrophoresis, Polyacrylamide Gel; D004596:Electroretinography; D005260:Female; D005654:Fundus Oculi; D017353:Gene Deletion; D005796:Genes; D014644:Genetic Variation / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010375:Pedigree; D010641:Phenotype; D012160:Retina / Q000473:pathology / Q000503:physiopathology