Visual evoked response asymmetry only in the albino member of a family with congenital nystagmus.
OBJECTIVE
To examine the purported relationship between visual fiber misrouting and congenital nystagmus (CN) by studying a family containing members with either hereditary CN alone or in conjunction with albinism.


METHODS
Eight relatives in three generations of a family with two genetic disorders (congenital nystagmus [CN] and albinism) underwent complete ophthalmologic examination and visual evoked potential (VEP) assessment of visual pathway organization using a luminance flash and checkerboard pattern onset/offset stimulus paradigm. Age-matched controls patients (albino, CN, or normal) corresponding to the three affected family members underwent the same procedure.


RESULTS
The standard VEP albino misrouting test did not reveal any signs of abnormality in all family members tested except for the clinically diagnosed 8-month-old albino proband patient. Visual evoked potential assessment from the albino patient evinced contralateral asymmetry characteristic of aberrant temporal retinostriate projections.


CONCLUSIONS
Although CN and albinism share some of the same clinical symptoms, these findings indicate that the disorders may be inherited and manifested independently in members of one family. Furthermore, the functional and/or structural factors responsible for CN cannot be readily ascribed to VEP retinal-cortical misprojections recorded in albinism.
Shallo-Hoffmann
J
J
Department of Strabismology and Neuroophthalmology, University of Göttingen Eye Hospital, Germany.
Apkarian
P
P
D000328:Adult; D000368:Aged; D016115:Albinism, Oculocutaneous / Q000235:genetics / Q000503:physiopathology*; D002675:Child, Preschool; D005074:Evoked Potentials, Visual; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009759:Nystagmus, Pathologic / Q000151:congenital* / Q000503:physiopathology*; D010364:Pattern Recognition, Visual; D010375:Pedigree; D010775:Photic Stimulation; D014795:Visual Pathways