Abstract
BACKGROUND: Myopia is a very common condition and a significant public health problem in China. The objective of the study was to explore the genetic influence on myopia in Mainland China school-aged children in Beijing. METHODS: In 2008, the data from 15,316 Chinese school students aged 6-18 years from 19 randomized schools in Beijing were analyzed to evaluate genetic influence on myopia in children. Heritability was calculated by mid-parent-offspring regression and parent-offspring regression. RESULTS: The estimate of heritability was 0.30 (95% CI, 0.27-0.33) for refractive value (RV). The adjusted mean refractive error was -2.33D (95% CI, -2.45 to -2.21) in children with two myopic parents compared with -1.13D (95% CI, -1.78 to -1.08) in children with no parental myopia. The adjusted odds ratio (OR) was 2.83 (95% CI, 2.47-3.24) in children with two myopic parents compared with no parental myopia. CONCLUSION: The study found a strong association between parental history of myopia and genesis of myopia in the offspring even after adjusting for environmental factors.