Effect of genetic predisposition on the age of onset and progression of myopia among medical students

Background: Nearsightedness, or myopia, one of the refractive errors of eye and it has become more prevalent in recent years. Heredity and visual stress are the two main factors responsible for the development of myopia. Medical students are more vulnerable to early onset of myopia. Aims and Objective: To analyze the commencement and progression of myopia with or without genetic predisposed medical students. Material and Methods: This study included 131 myopic students with the age range of 17–25 years. The subjects were grouped into genetically predisposed (with either of the parent or both parents myopic) and genetically non-predisposed (both parents non-myopic). The data regarding the age of onset, family history, and the refractory power at the onset and present were collected by validated questionnaire. Result: In genetically predisposed group, the early age of onset (11.03 ± 3.40 versus 12.98 ± 3.78), refractive power (right eye: 1.01 ± 0.96 versus 0.91 ± 0.57; left eye: 0.94 ± 0.71 versus 0.80 ± 0.62) was significantly increased (P < 0.05) when compared to the non-genetically predisposed group. Progression of refractive power showed a nonsignificant increase in the genetically predisposed group. Conclusion: Early age of onset and faster progression of myopia in genetically predisposed might be due to the combined influence of genetic predisposition and environmental factors.