Emily Winnicki | 2025 I.S. Symposium

Name: Emily Winnicki
Title: The Plague (Yersinia Pestis) in China: From Historical Perspectives to Modern Day Genetics
Majors: Anthropology; Biology
Minors: Archeology; History
Pathway: Museum & Archival Studies
Advisors: Dean Fraga; Margaret Ng Wee-Siang

While ancient DNA (aDNA) evidence and western primary sources have suggested an eastern origin for the second plague pandemic, little research has been done in English to understand the impact of the plague (Yesinia pestis) on China. My study looks to understand how the plague impacted life and medical literature in China at the time of the pandemic and how it might have changed human genetics through the process of natural selection. Using primary and secondary sources, I determined a tentative timeframe to be used in the computational portion of my project. Using methods previously used in studies focusing on European populations, I calculated pairwise FST values, a measure of genetic variability, between a pre-plague and post-plague cohort. Finally, de novo sequencing of a singular nucleotide polymorphism (rs922452) was compared with self-reported ancestral information. While the result demonstrates a change in genetic variation over time, I was unable to determine if these changes were the result of natural selection from the plague. Other explanations for these changes include sampling error, and other forces of evolution such as gene flow and genetic drift. This study provides a starting point for future research asking if the plague caused natural selection to occur in Chinese populations and demonstrates the importance of interdisciplinary, collaborative research.

Posted in Symposium 2025 on May 1, 2025.