Epigenome ‐wide association of PTSD from heterogeneous cohorts with a common multi‐site analysis pipeline

The objective of this consortium is to increase the analytical sample size by pooling data and combining expertise so that DNA methylation patterns associated with PTSD can be identified. Several quality control and analytical pipelines were evaluated for their control of genomic inflation and technical artifacts with a joint analysis procedure established to derive comparable data over the cohorts for meta‐analysis. We propose methods to deal with ancestry population stratification and type I error inflation and discuss the advantages and disadvantages of applying robust error estimates. To evaluate our pipeline, we report results from an epigenome‐wide association study (EWAS) of age, which is a well‐characterized phenotype with known epigenetic associations. Overall, while EWAS are highly complex and subject to similar challenges as genome‐wide association studies (GWAS), we demonstrate that an epigenetic meta‐analysis with a relatively modest sample size can be well‐powered to identify epigenetic associations. Our pipeline can be used as a framework for consortium efforts for EWAS.
Source: American Journal of Medical Genetics Part B: Neuropsychiatric Genetics - Category: Genetics & Stem Cells Authors: Tags: RESEARCH ARTICLE Source Type: research