Choroideremia: new findings from ocular pathology and review of recent literature.
Histopathology of young individuals affected by choroideremia is rarely available to allow correlation with the clinical presentation. A 30-year-old man with choroideremia died in a motor vehicle accident and one eye was subjected to histopathological examination. Immunoblot analysis of protein derived from white blood cells of a living brother, also affected with choroideremia, confirmed the absence of Rab escort protein-1, the normal CHM gene product. Direct sequencing of the coding region and adjacent splice sites of the CHM gene was undertaken on genomic DNA from the living brother and revealed a transition mutation, C to T, in exon 6 (R253X) which resulted in a stop codon and was predicted to truncate the protein product. Histopathological examination of the eye of the deceased brother showed relative independent degeneration of choriocapillaris, retinal pigment epithelium, and retina, similar to observations in the mouse model of choroideremia. In addition, mild T-lymphocytic infiltration was found within the choroid. The ophthalmic features and the pathology of choroideremia are discussed in light of new findings in the current case.
Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892-1860, USA.
Ian M
IM
MacDonald
Laurie
L
Russell
Chi-Chao
CC
Chan
D000063:Accidents, Traffic / Q000401:mortality; D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics*; D000328:Adult; D015794:Choroideremia / Q000235:genetics* / Q000473:pathology*; D018388:Codon, Terminator / Q000235:genetics*; D006801:Humans; D008297:Male
D048868:Adaptor Proteins, Signal Transducing; C081787:CHM protein, human; D018388:Codon, Terminator