Date of Award

January 2023

Document Type

Open Access Thesis

Degree Name

Master of Public Health (MPH)


School of Public Health

First Advisor

Andrew DeWan


This study aimed to describe the overlap between genetic variants that are independently associated with COPD and asthma, then dissect the cross-phenotype associations to characterize patterns of pleiotropic effects. The COPD and asthma datasets were separately extracted from an aging population consisting of white European subjects from the UK Biobank database. Genome-wide association tests were performed separately with the COPD and asthma data to first investigate significant genetic variants independently associated with each of the two phenotypes. With the GWAS summary statistics, several significant genetic loci that exhibit potential pleiotropic effects on COPD and asthma on a genome-wide significant level were identified. Lastly, to further characterize the pleiotropic effects, mediation analyses were performed to distinguish if these significant loci act directly on COPD and asthma, or if the cross-phenotype associations were predominately due to mediation through one of the phenotypes. The mediation analysis results suggested that the genetic effects of the pleiotropic loci on COPD were partially mediated by asthma, yet, at the same time these genetic loci also affect COPD and asthma directly and independently. The observed cross-phenotype associations with COPD and asthma could be explained as a combination of biological pleiotropy and incompletely mediated pleiotropy


This is an Open Access Thesis.

Open Access

This Article is Open Access