Preparation for Allele Swapping

This summer, I am researching possible mechanisms behind speciation in the yeast Saccharomyces paradoxus. I hope to determine if the evolution of sexual adhesin genes, which are required for sexual reproduction, drives speciation. Recently, there was a migration of a Saccharomyces paradoxus population from Europe to North America. This migrant population has displayed evidence of speciation in its mating preferences. In my project, I am analyzing the mating behaviors of North American, European and migrant strains after switching sexual adhesin alleles among the different populations.

These past few weeks of research have been pretty busy. My lab partner and I tied up some loose ends from our spring semester project, and I’ve transitioned from performing computational research to lab work, learning molecular and microbiology techniques. Currently, I am trying to get a transformation to work.

At the beginning of June, my lab partner and I looked back at our most recent project: computationally determining the rates of evolution of certain families of genes in the yeast Saccharomyces paradoxus. Unfortunately, we found that our results had not been consistent. We were getting different rates of evolution for the same genes when we used various programs to calculate these rates. However, after analyzing our data a bit more, my lab partner was able to find some errors in our technique. Our data is now consistent among different programs and supports our initial hypothesis: the sexual adhesin family of genes has greater rates of evolution than other families of genes.

A couple of weeks ago, I began to learn some of the techniques I need to perform the allele swaps for my project. I learned about the logic behind PCR (Polymerase Chain Reaction), a method for amplifying certain segments of desired DNA. I’ve also begun to perform transformations, a method for transferring DNA into a microbial species.

I’ve learned quite a bit this summer, and I’m excited to continue working in the lab. Hopefully my technique will improve as I continue working on my transformations.


  1. anwesterhaus says:

    This is super cool that you are able to witness evolution in progress! I was wondering what your reasoning behind your hypothesis is. Would you think that genes involved in sexual reproduction would evolve faster because genes for more efficient reproduction would spread more quickly through the population? Looking forward to your next update.
    -Anna Westerhaus

  2. Your research sounds so interesting and I am very impressed that you found the results you did! I also learned how to do PCR this summer, but a type called RAPD-PCR which is better for virus genomes. I think it is particularly cool that you found that sexual reproduction genes evolved faster for multiple strains! Do you think there are any other gene families where it would be advantageous to evolve more quickly? Good luck with the rest of your research!