Evolution and Medicine a New Approach for High School Biology

Transcription

1 LIVE INTERACTIVE YOUR DESKTOP Evolution and Medicine a New Approach for High School Biology May 10, 2011

2 Evolution and Medicine a New Approach for High School Biology Paul Beardsley May 10, 2011

3 Section I Introduction

4 Biological Sciences Curriculum Study Established in 1958 Nonprofit organization Three main areas of emphasis Curriculum Development Professional Development Research and Evaluation

5 NIH Curriculum Supplement Series Free curriculum supplements

6 NIH Evolution and Medicine Sponsored by: National Institute of General Medical Sciences National Institute of Neurological Disorders and Stroke National Eye Institute National Heart, Lung, and Blood Institute National Institute of Allergy and Infectious Diseases National Institute on Drug Abuse National Institute of Dental and Craniofacial Research National Institute on Aging National Cancer Institute National Center for Research Resources Office of the Director

7 What features would you like to see in a short curriculum that focuses on evolution?

8 Evolution is Relevant Hillis 2007 Ten Ways to Improve Evolution Coverage in Biology Textbooks 1. Demonstrate that evolutionary research is current and ongoing 3. Use fresh examples. 4. Show how evolution is relevant to human lives.

9 Let s pause for questions from the audience

10 Section 2 Overview of Evolution and Medicine

11 Engage: Ideas about the role of evolution in medicine Students provide initial explanations for the evolution of MRSA. Students examine data from Pax6, consider how common ancestry explains the value of model organisms. Adapted from: Washington NL, Haendel MA, Mungall CJ, Ashburner M, Westerfield M, et al Linking Human Diseases to Animal Models Using Ontology-Based Phenotype Annotation. PLoS Biology 7(11): e doi: /journal.pbio

12 Explore: Investigating Lactose Intolerance and Evolution Students investigate lactase persistence in humans Perform a lab experiment Provide initial explanations for patterns Study the genetic basis for lactase persistence Compare alternative hypotheses

13 Explain: Evolutionary processes and patterns inform medicine Students solve a medical mystery involving alphathalassemia Apply natural selection to explain the disease s high incidence.

14 Explain: Evolutionary processes and patterns inform medicine Students compare sequences across species for gene associated with cleft palette. Students explain the results in terms of common ancestry Explain how natural selection conserved certain sequences

15 Elaborate: Using evolution to understand influenza Align sequences of the hemagglutinin gene Learn about the hemagglutinin region and the immune system Relate principles of natural selection to the need for new vaccines

16 Evaluate: Evaluating evolutionary explanations Students evaluate an article about the evolution of vitamin C synthesis written for a school publication Compare each example of natural selection encountered in the supplement.

17 Let s pause for questions from the audience

18 Section 3 Lesson 1 Anaridia: An Eye Disease

19 Students learn about the rare disease aniridia, caused by mutations in Pax6. Students investigate data on Pax6 and contribute their ideas.

20 What can you infer about the Pax6 gene from the protein sequences from these four species?

21 Adapted from: Washington NL, Haendel MA, Mungall CJ, Ashburner M, Westerfield M, et al Linking Human Diseases to Animal Models Using Ontology-Based Phenotype Annotation. PLoS Biology 7(11): e doi: /journal.pbio On the basis of the pictures, do you think the function of the Pax6 gene is similar in all four species? Explain your reasoning.

22 Transition to model species Does the evolutionary tree suggest that the mouse is more closely related to the zebrafish or the fruit fly? How would students answer? A. Zebrafish B. Fruitfly C. Don t know

23 Do you think that the common ancestor of fruit flies, zebrafish, mice, and humans had a gene similar to Pax6?

24 How does shared ancestry explain why scientists can use model organisms to learn about human health?

25 Let s pause for questions from the audience

26 Section 4 Lactose Intolerance and Evolution

27 Explore: Investigating Lactose Intolerance and Evolution Students hear about an Asian teenager who moved to the US and began to suffer digestive problems after consuming milk. Investigate simulated lactase samples from patients around the world

28 Lesson 2: Lactose Intolerance and Evolution Working site

29 Lesson 2: Lactase Intolerance and Evolution Working site

30 Lesson 2: Lactase Intolerance and Evolution Working site

31 Gender

32 Age

33 What type of mutation causes the difference between lactase persistence and lactase nonpersistence? A mutation to the coding region for the lactase enzyme A mutation to a regulatory region for the production of lactase

34 Scientists have identified specific mutations that cause lactase persistence

35 Thinking about genetics What does it mean for the evolution of lactase persistence if all people who are lactase persistent don t have Mutation 1?

36 Explaining the Evolution of Lactase Persistence 1.Culture-historical hypothesis: In populations that herd and milk cows, goats, or camels, lactase persistence provides a selective advantage due to a higher level of nutrition or increased access to water

37 Explaining the Evolution of Lactase Persistence 2. Calcium hypothesis: Vitamin D helps the body absorb calcium. We can make vitamin D when UV light penetrates the skin. Lactose also helps the body absorb calcium found in milk. In populations exposed to low levels of UV light, lactase persistence provides a selective advantage (higher level of calcium)

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39 Figure 1: The following image shows the average daily ultraviolet (UV) exposure across Earth s surface. Darker colors indicate greater UV exposure. Image copyright George Chaplin. Adapted with permission. American Journal of Physical Anthropology, 107(2), 1998, pp Copyright 1998 Wiley-Liss, Inc.

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41 Approximate Time period Number of skeletons examined Possible cases of rickets 3000 BCE 616 6* CE CE CE * Some researchers interpret these skeletons differently and claim that they do not show evidence of rickets.

42 Let s pause for questions from the audience

43 Section 5 Using Evolution to Guide Research

44 Students learn about cleft lip and palate Gene Irf6 is associated with one form of cleft lip and palate Irf6 is active in mice as sides of mouth fuse

45 Goal: identify sections of the Irf6 gene that have remained the same over large amounts of time.

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49 Species Time since common ancestry with humans (millions of years) Nucleotides that are the same (number) Similarity with human sequence (%) Chimpanzee 8 1, Orangutan 15 1, Rhesus 30 1, monkey Dog 97 1, Horse 97 1, Cat 97 1, Cow Rat Mouse Guinea pig Armadillo 105 1, Opossum

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51 How much time is involved in the comparison of all four species? A 30 million years B 20 million years C 10 Million years D None of these

52 Questions about how to calculate time for an evoprint?

53 Imagine you had an evoprint with these four species. How much time would be represented in this evoprint?

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56 Advanced classes: 3 rd position in codon

57 How does evolution explain why certain regions of the Irf6 gene have not changed over large amounts of time?

58 Let s pause for questions from the audience

59 Thank you! 5415 Mark Dabling Blvd Colorado Springs, Colorado E: W: P:

60 Thank you to the sponsor of tonight's Web Seminar: This web seminar contains information about programs, products, and services offered by third parties, as well as links to third-party websites. The presence of a listing or such information does not constitute an endorsement by NSTA of a particular company or organization, or its programs, products, or services.

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63 National Science Teachers Association Dr. Francis Q. Eberle, Executive Director Zipporah Miller, Associate Executive Director Conferences and Programs Al Byers, Assistant Executive Director e-learning NSTA Web Seminars Paul Tingler, Director Jeff Layman, Technical Coordinator LIVE INTERACTIVE YOUR DESKTOP