Analyzing the genetic structure of populations: individual assignment
We'll spend the first 10-15 minutes of lecture illustrating two approaches to estimating F-statistics from data. As you'll see, the Weir and Cockerham is preferable. I present Nei's approach, because you'll still encounter it sometimes, and because presenting it helps me make the distinction between statistical sampling and genetic or evolutionary sampling.
After we finish our quick tour of F-statistics, I'll introduce an intriguing approach to analyzing population structure that doesn't require us to specify ahead of time which population any individual belongs to. It allows the data to tell us.
You may not realize it, but this kind of analysis has been in the news. Take a look at this article by Carl Zimmer from The New York Times.
- R Shiny app illustrating differences between Nei's Gst and Weir and Cockerham's Θ
Online notesAnalyzing the genetic structure of populations: individual assignment
Pritchard, J. K., M. Stephens and P. Donnelly. 2000. Inference of population structure using multilocus genotype data. Genetics 155:945-959 linkReturn to lecture schedule