• 3 out of 4 homozygotes were albino

• after being kept in constant light for more than 20 days less loss of photoreceptors occurred than in albino controls

• after 60 days in constant light the number of nuclei in the outer nuclear layer was reduced but still more than 4X that of albino controls

• did not occur in albino mice maintained in a normal light cycle unlike albino controls

• photoreceptor nuclei in the outer nuclear layer remainder normal unlike albino controls where the number is reduced

• regeneration of bleached rhodopsin required 18-24 hours as opposed to a more normal 1.5 hours

• little restoration of dark adaptation occurred in the 3 hours which was adequate for control mice

• cone recovery after bleaching was delayed by a factor of 2 relative to controls

• after being kept in constant light for more than 20 days less loss of photoreceptors occurred than in albino controls

• after 60 days in constant light the number of nuclei in the outer nuclear layer was reduced but still more than 4X that of albino controls

• 3 out of 4 homozygotes were albino