Gene mutation may explain why some people are averse to bright light
This means that strong light flashes could be disorientating, they say in a research paper in the journal Nature.
Dr Aart Kooijman from the University of Groningen said: 'These patients are essentially blind for seconds.'
The gene is involved in the activation and deactivation of photoreceptor cells in the eye - a key mechanism which helps the pupil to adjust in response to the strength of light it encounters.
The research teams found five people who complained of trouble dealing with bright lights, and discovered that they shared this flawed version of the gene.
Off the ball
Dr Kooijman said: 'In 1991, in the Netherlands, patients were identified with abnormal recovery from the influence of strong light flashes.
'For example, they reported difficulty in playing ball games because they could not see a moving ball.
'With sudden changes in luminance, like that caused by going from inside to outside on a sunny day, these patients are essentially blind for five to 10 seconds.'
Presently, the only solution is to wear dark glasses, but it is hoped the finding could help ophthalmologists explain the condition.
Dr Thaddeus Dryja, from Harvard Medical School, said: 'Quite a few people do complain of this.
'The ophthalmologist can now say there is something wrong, you are not crazy.'
He said: 'We found that their symptoms are due to defects in proteins that normally function to deactivate photoreceptors after exposure to light.
'The disease was due to mutations in the gene encoding these proteins.'
Gene mutaþie ar putea explica de ce unii oameni sunt potrivnic la luminã - Gene mutation may explain why some people are averse to bright light - articole medicale engleza - startsanatate