Disparity between central and peripheral refraction inheritance in twins

Area of Science:

• Ophthalmology
• Genetics
• Environmental Health

Background:

• Myopia incidence is rising in young people, linked to modern lifestyles and technology use.
• Increased exposure to risk factors like indoor time and close work contributes to this public health issue.
• Mechanisms of myopia development, particularly vitreous chamber enlargement and central/peripheral retinal interactions, require further understanding.

Purpose of the Study:

• To investigate the genetic and environmental contributions to refractive error across the retina.
• To analyze the variance in objective refractive error in relation to retinal location.

Main Methods:

• A classical twin study design was employed.
• Objective refractive error was measured across a 70° horizontal retinal arc in 100 university student twin pairs.
• Analysis focused on distinguishing shared environmental and additive genetic variances.

Main Results:

• Shared environmental factors explained most refractive error variance in the central retina (within 42°).
• Additive genetic variance predominated in the peripheral retinal areas measured.
• Environmental influence decreased, and genetic influence increased towards the retinal periphery.

Conclusions:

• Environmental exposures are the primary driver of refractive error variation in the macula-surrounding retina for young adults.
• Genetic factors become increasingly important for refractive error in the peripheral retina.
• Findings underscore the complex interplay between environment and genetics in myopia development across different retinal regions.