INTRODUCTION TO HUMAN GENETICS
Type of activity:
- Group activity
(requires much audience
- Slide presentation
- Biology (most applicable)
- Life Science
- Advanced/AP Biology
- Integrated Science
- Genetics, Biotechnology
What questions does this activity help students answer?
- Of what significance
is Genetics to ME?
- How am I different from others?
- (and more importantly) How am I LIKE others?
Notes for the teacher:
Students should have a basic understanding of Mendelian Genetics in order to get the most out of this activity. Slides were obtained from a series of slides from the Human Genetics Module of the Teacher Enhancement Program in Biology, University of Wisconsin-Madison, Genetics Building, Henry Mall, Madison, WI 53705. Contact Ruth Owens at 608/262-1006.
Required of students: A basic understanding of Mendelian Genetics.
Preparation time needed:
Once you have selected the slides you would like to use, your preparation time is minimal. Your script needs to be prepared based on your slides; the discussion will center around student comments and questions!
Class time needed:
I teach this lesson in one class period (52 minutes).
This is usually a lesson that takes the entire period, due to student questions and enthusiasm.
The purpose of this lesson is to foster interest and enthusiasm for the study of human genetics with students. The lesson consists of a slide presentation showing everything from common human genetic tendencies (eye color, widow's peak, etc.) to polydactyly. Emphasis is placed on celebrating our differences, yet realizing how very much we all are alike.
Materials needed: slide projector and screen, slides (see reference above).
Description of Activity:
The most interesting experience in my Biology classroom is my introduction to Human Genetics. My Genetics unit is, I believe, the most exciting unit of the school year (in both my eyes and the students' eyes!), and this introduction is one small part.
Prior to this activity, students have learned the basics of Mendelian Genetics. Students learn about Mendel as a man and a scientist; about the meticulous and numerous records he kept; and about the skepticism of the scientific community toward his work. The NOVA film, "Garden of Inheritance", is an excellent portrayal of Gregor Mendel's life and work, and we watch and discuss that video at length. After the students have a basic understanding of Mendelian Genetics, we are now ready to study Human Genetics, about which they have so much natural curiosity!
My introduction to Human Genetics consists of a discussion and slide presentation. (The slides are selected from a set obtained from a Human Genetics course sponsored by the Teacher Enhancement Program at the University of Wisconsin-Madison.) There are fewer than twenty slides, but the discussion we have fills each class period. The first slide shows various vegetables; I ask the students how these vegetables are different, and how are they similar? I then share with them a theme that is emphasized throughout the rest of the unit: Humans are very much alike, but we also have our differences; differences should be celebrated, but we should not forget our similarities. For example, a student with Down's Syndrome in the Cognitively Disabled classroom down the hall has many of the same needs, wants and desires as the freshmen in my biology classes. The tone is set, and we continue.
The next few slides show numerous variations in humans (eye color, widow's peak, etc.); students are quick to check their variations, and they are reminded that the lab the next day is about human variation and its relationship to genetics. The next few slides focus on genetic disorders that may affect a particular population (such as sickle cell anemia in the African-American population, cystic fibrosis as the most common genetic disease of the Caucasian population, and the sex-linked trait of colorblindness).
One particular slide shows a young African boy, sitting in a wagon, holding the wagon with both hands, and his bare feet hanging over the end of the wagon. Students are challenged to raise their hands when they notice anything that is different about the young man. They become very interested when they first notice he has polydactyly ("many digits"), which they initially note on his hands (each with six fingers); but soon, they notice he also has six toes on each foot as well. We discuss the genetics of the characteristic, how polydactyly is treated in our society, and what the societal implications would be if this young man were raised in Wisconsin. Students are quick to point out problems (or advantages!) with gloves, classes like keyboarding, and playing the piano.
One of the last slides shows a man's hands on the bottom of the slide and his son's hands on the top. Both the man and his son have a deformed left hand; students are quick to note the deformity, but not necessarily that both have a deformed LEFT hand. The true story (shared with us in the Human Genetics course; the man had sought information from a genetic counseling center in Madison) is then shared with my students. The man whose hands are pictured was born in Mexico, with his hand as they see it. His mother was told when her son was born that the deformity was her fault, as she had not attended church enough while she was pregnant. (At this point, we discuss other cultural beliefs, those that are scientifically founded and those which have no basis scientifically). The young man moved to WI in his twenties, married a young woman, and they had "Timmy", the boy whose hands are pictured. Upon receiving genetic counseling, the couple was informed that the hand deformity was definitely genetically transmitted. The man was able to call his mother in Mexico and explain to her, and help her get rid of the guilt she had carried with her for so many years.
The very last slide of the set is one of three people, on one side, and three dogs, on the other side. The resemblances of these people and their dogs are incredible! We close by discussing how important it is to celebrate our differences, but not to forget, as we study human genetics, how very much alike we all truly are.
Method of Evaluation:
Student discussion and participation during the discussion. In addition, many of the activities that follow this introduction involve concepts that have been presented here. Students are evaluated on much of this information during a Genetics Role-Play
Activity and a written exam, as well as in various lab activities that follow this introduction.
Many students choose to pursue a topic discussed during this introduction. In addition, students research a genetic disorder through a role-play activity that involves cooperative learning and student research. Other opportunities for extension are offered as students express an interest or need differentiation.