Do polygenic risk scores for alcohol dependence predict the presence of gambling disorder in individuals of European and African ancestry?

Labuschagne, Shelby Layla

Do polygenic risk scores for alcohol dependence predict the presence of gambling disorder in individuals of European and African ancestry?

Thesis / Dissertation

2023

Publisher

University of Cape Town

Department

Department of Biological Sciences

Faculty

Faculty of Science

Abstract

This study aimed to determine whether the calculation of polygenic risk scores (PRS) could indicate a genetic link between gambling and alcohol use disorder. The main objective of the study was to determine if PRS for alcohol dependence in one study (NESARC dataset) could be used to predict the presence of gambling disorder in another (Alcohol Dependence dataset). No prior published research was found which calculates PRS for a substance addiction and applies it to the prediction of a behavioural addiction. The software PRSice was used to generate the PRS for two datasets, and these were analysed using linear modelling to determine whether the PRS for alcohol dependence (in the NESARC GWAS dataset) could predict the presence of GD in individuals with alcohol dependence. The model indicated accurate linkage 4.79% of the time. Due to this low percentage, it was concluded that PRS for alcohol dependence cannot accurately and regularly predict the presence of gambling disorder in individuals of European and African ancestry. However, we recognize limitations of the study, for example in the small sample size.