Abstract
Purpose :
To explore the heritability, concordance and prevalence of ERM in a twin population.
Methods :
Macular OCT scans (Optovue iVue 100, Optovue, Freemont, CA) taken between 2014-2019 from participants of the TwinsUK cohort were graded for signs of ERM. Zygosity was ascertained using the “peas in a pod” questionnaire. Casewise concordance was calculated for mono- (MZ) and dizygotic (DZ) twin pairs using 2C/(2C + D), where C=number of twin pairs concordant and D=number of twin pairs discordant for ERM. The covariance of ERM within MZ and DZ twin pairs was compared, and genetic modelling techniques were used to determine the relative contributions of genes and environment to the variation in ERM and adjusted for age using OpenMx (http://openmx.psyc.virginia.edu/) package in R.
Results :
OCT scans from 1098 twin pairs (704 monozygotic [MZ] and 394 dizygotic [DZ]) aged 18-89 (mean 54 SD ±17) were analysed. ERMs were present in 250 individuals, prevalence 11.4%. 35 MZ and 13 DZ twin pairs were concordant for ERM. 80 MZ and 74 DZ twin pairs were discordant for ERM. Concordance was 0.47 and 0.26 for MZ and DZ twins, respectively, suggesting a role for genes. A model combining additive genetic and unique environmental effects provided the best fit and resulted in an ERM heritability estimate of 0.49 (95% CI, 0.38–0.64).
Conclusions :
This is the first classic twin study describing the concordance and heritability of ERM. The findings suggest that ERM has significant underlying genetic influences. Further research to better understand these genetics influences is needed.
This is a 2021 ARVO Annual Meeting abstract.