Smoking, dietary betaine, methionine, and vitamin D in monozygotic twins with discordant macular degeneration: epigenetic implications.

ABSTRACT:

Objective

We evaluated monozygotic twin pairs with discordant age-related macular degeneration (AMD) phenotypes to assess differences in behavioral and nutritional factors.

Design

Case series.

Participants

Caucasian male twin pairs from the United States Twin Study of Macular Degeneration.

Methods

Twin pairs were genotyped to confirm monozygosity. Ocular characteristics were evaluated based on fundus photographs using the Wisconsin Grading System and a 5-grade Clinical Age-Related Maculopathy Staging System. We selected twin pairs discordant in each of the following phenotypic categories: Stage of AMD (n = 28), drusen area (n = 60), drusen size (n = 40), and increased pigment area (n = 56). The Wilcoxon signed-rank test and linear regression were used to assess

SUBMITTER: Seddon JM 

PROVIDER: S-EPMC3711586 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature