Power and sample size estimation for epigenome-wide association scans to detect differential DNA methylation.

ABSTRACT:

Background

Epigenome-wide association scans (EWAS) are under way for many complex human traits, but EWAS power has not been fully assessed. We investigate power of EWAS to detect differential methylation using case-control and disease-discordant monozygotic (MZ) twin designs with genome-wide DNA methylation arrays.

Methods and results

We performed simulations to estimate power under the case-control and discordant MZ twin EWAS study designs, under a range of epigenetic risk effect sizes and conditions. For example, to detect a 10% mean methylation difference between affected and unaffected subjects at a genome-wide significance threshold of P = 1 × 10^-6, 98 MZ twin pairs were required to reach 80% EWAS power, and 112 cases and 112 controls pairs were needed in the

SUBMITTER: Tsai PC 

PROVIDER: S-EPMC4588864 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature