Population Genetics |
BIOL 4260
Population Genetics
University of Vermont
Population Genetics (Spring 2025);
Lecture
Aiken 112; Tuesday and Thursday, 10:05 am - 11:20 am
Recitation (pick one):
Option 1: Tuesday, 11:40 am - 12:30 pm in ROWELL HALL 115
Option 2: Thursday, 11:40 am - 12:30 pm in L/L-A A161
Course Description: This course explores the dynamics shaping the genetic basis of heritable biological variation, and their importance for understanding the world around us. This is critical knowledge for biology professionals since the processes that give rise to colorful animal variation are the same allowing viruses and bacteria to develop antibiotic resistance. We will explore the biological and mathematical underpinnings of two major processes in evolution: natural selection and genetic drift, both in the backdrop of other forces that create genomic complexity (e.g., mutation and structured populations).
Course Expectations: This upper-division course assumes students have a basic understanding of biological principles. This course will use elementary algebra and arithmetic, as well as statistics and probability, to transform concepts in biology into numerical models from which to derive predictions about the natural world. This course is designed for students with advanced knowledge of biology and a basic understanding of mathematics. Thus, students are not expected to have advanced mathematics skills, and all the required math tools will be reviewed during the course. The course has a recitation component where students will engage in advanced discussion of the primary research literature.
Topics:
The course is divided into six modules, as follows:
Part 1: Introductions and Review. During the first 2-weeks of the course, we will spend some time building and refining a shared vocabulary for the class. To this end, we will have a refresher on genetics, statistics, and the principles of the Hardy-Weinberg model
Part 2: Single locus model of natural selection. We will dive into the dynamics of natural selection through the lenses of the single locus, deterministic, discrete generation model. We will derive the dynamics of selection from the Hardy-Weinberg model under various coefficients of dominance. We will dive deeper into issues of the “speed” and the “direction” of selection, culminating in discussions of directional vs. balancing selection. After mastering the basic model, we will introduce the concept of random mutation into the model to discuss the dynamics of mutation-selection balance.
Part 3: Single locus model of genetic drift. In part three of the course, we will take a deep dive into the dynamics of genetic drift. For this module, we will introduce the “Wright-Fisher” model. In particular, we will discuss the dynamics of evolutionary sampling in finite populations, the decay of heterozygosity, mutation-drift equilibrium, effective population size, and “the coalescent”.
Part 4: Multilocus natural selection models. After mastering the basic single locus models (selection + drift), we will turn our attention to multilocus models of evolution. We will explore the concepts of linkage disequilibrium and linked selection.
Part 5: Demography and drift in structured populations. Parts 1-4 of the course operate under a series of simplifying assumptions whereby species do not experience “spatial contexts,” and thus, gene flow or migration cannot occur. Part 5 of the course will introduce the idea of spatially explicit gene flow as well as other interesting phenomena such as inbreeding and “selfing”.
Part 6: Molecular Evolution and patterns of variation. In the last portion of the course, we will learn about theories that integrate aspects of selection and drift that have been foundational to biology. In particular, we will discuss the principles of the Neutral Theory of Evolution as well as the “footprints” of natural selection in genomes.
