First Author: M.He CHINA
Co Author(s):
Purpose:
To estimate the heritability of peripheral refraction in Chinese children and adolescents.
Setting:
: Twin cohort in Guangzhou
Methods:
We examined 72 monozygotic (MZ) twins and 48 dizygotic (DZ) twins aged 8 to 20 years from a population-based twin registry. Temporal and nasal peripheral refraction, each 40 degrees from the visual axis, as well as axial refraction, were measured using a Shin-Nippon NVision–K5001 auto-refractor. Relative peripheral refractive error (RPRE) was defined as the peripheral refraction minus the axial refraction. Heritability was assessed by structural equation modeling after adjustment for age and sex.
Results:
The mean and standard deviation of temporal refraction (T40), nasal refraction (N40), RPRE-T40, RPRE-N40 and T40-N40 asymmetry were -0.27±2.0 D, 0.36±2.19 D, 1.18±1.39 D, 1.80±1.69 D and -0.62±1.58 D, respectively. The intra-class correlations for T40 refraction, N40 refraction, RPRE-T40, RPRE-N40 and T40-N40 asymmetry were 0.87, 0.83, 0.65, 0.74 and 0.58 for MZ pairs, and 0.49, 0.42, 0.30, 0.41 and 0.32 for DZ pairs, respectively. A model with additive genetic and unique environmental effects was the most parsimonious, and the heritabilities were 0.84, 0.76, 0.63, 0.70, 0.55 for the above-mentioned peripheral refractive parameters, respectively.
Conclusions:
Additive genetic influences explained most of the variance in peripheral refraction. Genetic effects play a similar role both in the axial and peripheral refraction.
Financial Disclosure:
No
