The role of genetics in myopia development

Nature v nurture: It’s a question which affects so many developmental debates as paediatricians, physicians, and others seek to understand the physical and mental changes which an individual may encounter on their road to adulthood. In some instances, the answer may be obvious; but in others, the debate rolls on, with theories being formed and reformed as our knowledge of genetics and the environment grows.

Take myopia, for example. The tendency for myopia to run in families may, at first sight, suggest that genetics plays a part in its development. But could that link be less nature and more nurture? It has been shown that close work can be a trigger for myopia, so are families with myopia more likely to be book readers or to spend a lot of time on computers?

One of the ways in which researchers might test a link is to undertake a review of twins. If both twins have myopia, does that strengthen the argument for a genetic link? Well, it might do, but here again, we are back with the book/computer argument. And if only one twin has marked myopia, does that argue against an inherited condition? Well, it might do, but one twin may be bookish and one sporty, and it is known that time spent outdoors can help to reduce the development of myopia.