The occurrence of pigmentary degeneration of the retina, heredomacular degeneration, and retinitis punctata albescens in "unaffected" members of families with hereditary ataxia has been subjected to two possible interpretations. The first is that these conditions are equivalents (or alternate expressions of the same gene) of Friedreich's disease.1 The second is that the two groups occur coincidentally in the same family.2
The present study concerns a family of 415 members wherein retinal degeneration and Friedreich's ataxia with heart disease are known to occur. Of the 363 living members, 160 were examined for evidence of neurological, ophthalmological, cardiac, and musculoskeletal defects. The ophthalmological findings of the study are reported herein.
Protocol and Comments on the Family Studied
Inquiry was made of each of the 160 persons examined (or, in the case of children, their parents) as to past medical history, with particular attention paid to history of infectious disease, trauma,
HECK AF. Presumptive X-Linked Intermediate Transmission of Retinal DegenerationsVariations and Coincidental Occurrence With Ataxia in a Large Family. Arch Ophthalmol. 1963;70(2):143-149. doi:10.1001/archopht.1963.00960050145002