Master’s Defense for Adelle Price

Friday November 18, 2022, 3:00 pm – 5:00 pm in Student Commons 4017

Title: Detection of Fine-Scale Population Structure in Genetic Summary Data with Summix

Committee: Audrey Hendricks (advisor), Joshua French, Chris Gignoux

Abstract: Publicly available genetic summary data is used in research and clinical settings to identify potential causal variants, build polygenic scores, and leverage common controls. However, the utility of publicly available data is limited for understudied and admixed populations as genetic summary data can mask population structure. Population structure, here, refers to a difference in allele frequencies between populations due to genetic ancestry. The Summix method was developed to estimate and adjust for ancestry in genetic summary data at the continental ancestry level. Here, we assess the ability of Summix to accurately and precisely estimate fine-scale ancestry proportions in genetic summary data from gnomADv3.1.2 genome continental ancestries (e.g. East Asian, African) using up to 52 fine-scale reference groups. Given a minimum per fine-scale reference ancestry sample size of 20, we find that Summix estimates fine-scale ancestry with an accuracy of at least ~94.0% and a precision of at least ~99.8%. Additionally, we develop an algorithm to identify missing fine-scale reference ancestries in a given reference ancestry panel. The ability of Summix to estimate fine-scale genetic ancestry will increase the utility of publicly available genetic summary data by allowing for more precise matching of ancestry between cases and controls, or even individuals to a given public dataset.

Zoom link: Please contact MathStats-staff@ucdenver.edu for Zoom url