1 / 14

Our Test Organism

Our Test Organism. Drosophila simulans. Trait of Interest. Red vs. White Red = advantageous “mutation” Why are red eyes advantageous? Sensory perception White eyes = reduced mate tracking. Drosophila chromosome. What are we going to look at?. Two markers on X-chromosome

calder
Download Presentation

Our Test Organism

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Our Test Organism Drosophila simulans

  2. Trait of Interest Red vs. White Red = advantageous “mutation” Why are red eyes advantageous? Sensory perception White eyes = reduced mate tracking

  3. Drosophila chromosome What are we going to look at? • Two markers on X-chromosome • One close to the gene for white eyes • One far from the gene for white eyes • Why are we going to look at 2 markers? Red / White eye color gene 22 million bases of DNA 22 million bases of DNA “Near” “Far”

  4. Microsatellites & Genetic Markers Sequence differences (aka variation) between alleles Usually base pair repeats, insertions, or deletions Used for between & within-species comparisons

  5. Before sweep After sweep Selective Sweep/Hitchhiking This is one chromosome from 12 different people. The different colors represent different alleles for that gene. What happened?

  6. How are we going to observe & measure genetic variation?

  7. Step 3: Introduce “advantageous mutation” Allow mating for several generations

  8. Anesthetizing fliesFlyNap – Stinky!

  9. White male Red female White female Red male Sexing your flies: males have a “black butt”, females have large white abdomen

  10. How to tell males from females • Males have black abdomens • Look close at the tip of the male abdomen and you will see his junk • Females have rounded abdomens Female Male

  11. Sexing Female Male

  12. Our Treatments • Control group: • 5 white-eyed males, 5 white females • Experimental group: • 5 white-eyed males, 5 white females, 1 red male (“mutant”)

  13. Started with this… Control group: 5 white-eyed males, 5 white females Experimental group: 5 white-eyed males, 5 white females, 1 red male

  14. After 1 Generation, you will sort the flies On a white piece of paper…. Sort into categories and count

More Related