GENETIC-MAPPING OF A CONE AND ROD DYSFUNCTION (ALAND ISLAND EYE DISEASE) TO THE PROXIMAL SHORT ARM OF THE HUMAN X-CHROMOSOME

A five generation family with an X linked ocular disorder has been inv estigated. The major clinical features were reduced visual acuity, nys tagmus, and myopia. Although impaired night vision was not a symptom, using psychophysical and electrophysiological testing both rod and con e function were found to be abnormal in all affected males. No abnorma lity was detected in carrier females. Gene location studies showed X l inked transmission of a gene that maps to proximal Xp11. The findings observed in this cohort are similar to those previously reported in bo th congenital stationary night blindness type 2 (CSNB2) and Aland Isla nd eye disease (AIED). This study addresses whether CSNB2 and AIED are a single entity or whether the latter is a subset of the former.