Myopia

I've been thinking about the matter of myopia, and how research is constantly trying to prove whether it's a genetic or environmental matter. While I can understand the merits of trying to prove the origins of myopia, I do wonder if there's a chance that it's really a combination of the two.

For example, it was found that there was a probable genetic predisposition to myopia. Yet, other research has found that there's a positive correlation between myopia prone environments (lots of close work) and people there, regardless of their lineage. It sounds to me that there's a mix of genetics and environment here, where those genetically prone to myopia are more likely to develop serious myopia when exposed to a myopic environment, while everyone else are prone to develop it regardless of genetics due to the environment.

If I were to consider possible physical attributes that predispose one to myopia, I'd go with eyeball shape and memory. Students with good memory may not study nearly as much as the others with poorer memories, and become more unlikely to develop myopia from excessive close work. And those with certain eyeball shapes are already predisposed to the eyes growing lopsidedly to create the visual imperfection, and are thus more likely to develop myopia from close work. Obviously, a combination of the two would indicate the predisposition towards severe myopia.