TY - JOUR
T1 - The heritability of the ring-like distribution of macular pigment assessed in a twin study
AU - Tariq, Ambreen
AU - Mahroo, Omar A
AU - Williams, Katherine
AU - Liew, Sh Melissa
AU - Beatty, Stephen
AU - E Gilbert, Clare
AU - Van Kuijk, Frederik J
AU - Hammond, Christopher J
PY - 2014
Y1 - 2014
N2 - Purpose. It has been suggested that ring-like patterns of macular pigment, as measured with dual wavelength autofluorescence, are observed less frequently in subjects with age-related maculopathy. We explored relative contributions of genetic and environmental factors in macular pigment distributions using a classic twin study. Methods. 322 healthy Caucasian female twins, aged 16-50 (mean 40) years, underwent measurement of macular pigment (MP) optical density by two-wavelength fundus autofluorescence as part of a previous nutritional study. In the present study, the right eye MP profile was assessed for the presence of a ring-like pattern by two graders independently, using common criteria, with a third grader arbitrating in cases of disagreement. Concordance was calculated as 2C/(2C+D), where C is the number of twin pairs concordant, and D the number discordant, for the ring-like pattern. Also, heritability was calculated using maximum likelihood structural equation modelling. Results. Images and zygosity data were available for 314 twins (88 monozygotic (MZ) and 69 dizygotic (DZ) pairs). The overall prevalence of the ring pattern was 25.8%. Respective concordances for MZ and DZ twins were 0.75 and 0.22. Additive genetic factors were estimated to contribute to 84.0% of the total variance (95% confidence intervals, 63.7% - 94.6%). Conclusions. Concordance for monozygotic twins was over 3 times that for dizygotic twins, with heritability estimated at 84%, indicating that genetic factors contribute to the development of the ring structure.
AB - Purpose. It has been suggested that ring-like patterns of macular pigment, as measured with dual wavelength autofluorescence, are observed less frequently in subjects with age-related maculopathy. We explored relative contributions of genetic and environmental factors in macular pigment distributions using a classic twin study. Methods. 322 healthy Caucasian female twins, aged 16-50 (mean 40) years, underwent measurement of macular pigment (MP) optical density by two-wavelength fundus autofluorescence as part of a previous nutritional study. In the present study, the right eye MP profile was assessed for the presence of a ring-like pattern by two graders independently, using common criteria, with a third grader arbitrating in cases of disagreement. Concordance was calculated as 2C/(2C+D), where C is the number of twin pairs concordant, and D the number discordant, for the ring-like pattern. Also, heritability was calculated using maximum likelihood structural equation modelling. Results. Images and zygosity data were available for 314 twins (88 monozygotic (MZ) and 69 dizygotic (DZ) pairs). The overall prevalence of the ring pattern was 25.8%. Respective concordances for MZ and DZ twins were 0.75 and 0.22. Additive genetic factors were estimated to contribute to 84.0% of the total variance (95% confidence intervals, 63.7% - 94.6%). Conclusions. Concordance for monozygotic twins was over 3 times that for dizygotic twins, with heritability estimated at 84%, indicating that genetic factors contribute to the development of the ring structure.
U2 - 10.1167/iovs.13-13829
DO - 10.1167/iovs.13-13829
M3 - Article
C2 - 24609627
SN - 0146-0404
VL - N/A
SP - N/A
JO - Investigative Ophthalmology & Visual Science
JF - Investigative Ophthalmology & Visual Science
IS - N/A
M1 - N/A
ER -