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WEEK 1Learning Objective: Explain how gel electrophoresis is used in DNA fingerprinting for forensic science and paternity testing.

Learn about how DNA is used to identify an individual. We use DNA fingerprinting for paternity tests and criminal trials. In this lesson, you will do a virtual lab using gel electrophoresis to learn how the DNA fingerprinting process works. You will then see how the results of gel electrophoresis are used to identify a suspect at a crime scene. And finally, you will see how it is used to identify the father of a child.

1. Gel Electrophoresis Virtual Lab

https://learn.genetics.utah.edu/content/labs/gel/

Before starting the virtual lab, read through the questions below so you know what you need to understand in the end. Above is the link to the lab - go through the lab reading about all the components. When you are done, answer these questions.

1. What gets put into the "wells" of the gel?

2. Why does the DNA move through the gel?

3. Why does some DNA move farther through the gel than others?

4. What was the point of adding the "DNA size standard" to one of the wells?

5. Explain in a couple of sentences how the gel electrophoresis process works, demonstrating what you learned from doing the virtual lab.

Also... you can watch this video to learn more about this process: https://www.youtube.com/watch?v=ZDZUAleWX78

2. Using gel electrophoresis for DNA fingerprinting.

Watch this video first: https://www.youtube.com/watch?v=DbR9xMXuK7c

Note - no fingers are involved in this process. We call it a DNA fingerprint because fingerprints are something that are unique to each individual. A person's exact genetic code is also unique to an individual. So a DNA fingerprint is really just showing the genes that make a person unique.

Examine the gel below... note that DNA was collected from the victim involved in a crime scene and from two suspects. Can you compare their sequence and determine which suspect is guilty?

3. Use gel electrophoresis to determine who is the father of a child -- also known as a paternity test.

http://www.pbs.org/wgbh/aso/resources/guide/earthappenact3.html

READ: In this hypothetical paternity case, four autoradiographs show DNA "fingerprints" taken from three individuals: a mother, her child, and the child's alleged father. Each autoradiograph compares equivalent DNA segments from the three individuals. The two dark bands in each column represent one individual's DNA segments -- one inherited from that individual's biological mother and the other from the biological father. These segments differ in length from person to person; for this reason they are used as genetic markers. Here, each length is designated by a letter, A through O. The two letters associated with each segment indicate the individual's genotype.

  1. Instructions

    1. Under each column in the autoradiograph, write the letters associated with each individual's genotype. For example, the genotype of the mother in the first column is A/D. Then, circle the letter in the child's genotype that represents the gene inherited from the mother.

    2. Which "letters" must the child have inherited from its father?

    3. Based on this information, what evidence suggests that the alleged father could be biologically related to the child?

Check your answers here: http://www.pbs.org/wgbh/aso/resources/guide/earthappenact3.html

WEEK 2

Option 1: Smallpox reading

At the beginning of the year, we watched a video to learn about the history of vaccines and the eradication of smallpox I thought the triumph over this disease might give us some hope as we look for vaccine options and better diagnostic tools for Covid19. This is an excerpt from a book that tells a bit more of the story. The book gets really good reviews. Please excuse any mispronunciation of names on my part.

This book is now over 20 years old - the author I think is working on a revised edition -one that looks like it might be available digitally in Kobo. These links will be only be available this week. After this week I plan to delete them.

I decided to read it to you so that you could listen. It is broken up into 15 minute sections.

SMALLPOX -OF SCARS SCABS, ORPHANS, AND SPOTTY COWS from INVISIBLE ENEMIES-STORIES OF INFECTIOUS DISEASES

Assessment options: (Choose one)

  1. Write a 4-6 sentence summary for each 15 minute section with at least 2 specific facts from that section. Start with a topic sentence!

  2. For each term from the title, write a 1-3 sentence explanation of how this term relates to the history of smallpox.

    1. Scars

    2. Scabs

    3. Orphans

    4. Spotty Cows

  3. For each term from the title, draw a picture to demonstrate your understanding of how that term relates to the history of smallpox. (If what is occurring in your picture isn't obvious, write a short caption.)

    1. Scars

    2. Scabs

    3. Orphans

    4. Spotty Cows

Here are links to the 4 sections of readings:

https://youtu.be/EaAGtka4YxM

https://www.youtube.com/watch?time_continue=13&v=EaAGtka4YxM&feature=emb_logo

https://www.youtube.com/watch?v=Rd9DLxcujCo