He says: "The reasons for myopia are not well understood and changes in lifestyle which mean that we spend far more focusing on close objects, such as computer screens, mobile phones and books, are clearly a factor - but our study now suggests these lifestyle factors may only have a major effect on genetically susceptible people."

Dr Hammond urges parents: "Our research is great ammunition for mums and dads who are looking for ways to keep their children entertained during the long summer holidays - because it shows that children should balance any close reading with outdoor activities.

"Especially if both parents are myopic, I recommend as an ophthalmologist that you take a few simple steps to ward off the development of myopia - try moving the television further away from the sofa, don't let your children play computer games or surf the net for hours on end - and ensure that they get out of the house to enjoy the summer sun and play with friends."

--http://www.news-medical.net/?id=3691