Gene Screen - App Assignment write ups PDF

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App Assignment write ups...

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Gene Screen: An Analysis of the Genetics App for Secondary Education Claire Verhagen University of Victoria EDCI 767

The App The App I analyzed is called Gene Screen and was created by the Cold Spring Harbor Laboratory at the DNA Learning Centre. It is available at the iTunes App Store (free of charge) and is compatible with iPhones and iPads. The Gene Screen app is an educational tool for understanding inheritance patterns and probabilities associated with recessive genetic diseases. There are four mini-lessons (Figure 1) that educate the user on specific aspects of genetics (Genes and Inheritance, Population Genetics, Recessive Genetic Diseases, and Genetic Screening) and four inter-

active features (Figure 1) used to calculate inheritance (Genetic Traits, Genetic Diseases, Blank Punnett Square, and Jewish Genetic Diseases). (Figure 1: Home screen for Gene Screen App. Left: highlights mini-lessons. Right: highlights the interactive inheritance calculators.)

The mini-lessons have users tap through pages that explain the general topic (Figure 2). For example, the Genes and Inheritance lesson begins with “All living things, including humans, are made up of cells. The human body has about 100 trillion cells.” This text is accompanied by a simple video that starts with a picture of a person and zooms into an animated generalized cell. The mini-lesson goes on to talk about the nucleus, DNA, chromosomes, mutation, the genetics of sexual reproduction, and probabilities of inheritance. Each screen has a simple video that compliments the text.

The inheritance calculators allow users to drag potential parents onto the axes of a Punnett

square and then click a button to see the genetic possibilities of the offspring (Figure 2). Users can then click another button (mate) to see the app randomly select one of the potential offspring. (Figure 2: The Gene Screen. Left: a screen capture of a page within the Genes and Inheritance mini-lesson. Right: a screen capture of the Genetic Diseases inheritance calculator.)

There are also two features in Gene Screen that discuss how recessive genetic diseases are disproportionately represented around the world. The Jewish Genetic Diseases (Figure 3) feature highlights recessive genetic diseases which affect the Ashkenazi Jewish population to a higher degree. The Map of Genetic Diseases feature (Figure 3) shows where a disease (selected from

the menu) is most prevalent in the world.

(Figure 3. Gene Screen. Left: the Jewish Genetic Disease feature. Right: the Map of Genetic Diseases feature.)

Curriculum Connections

This app could be used to teach the genetics unit of Science 10 and review basic principles for Anatomy and Physiology 12.

The Science 10 curriculum includes “DNA structure and function, genes and chromosomes, and simple patterns of inheritance” [2] in the required content—all of which are introduced in the Gene and Inheritance mini-lesson on the app. In addition, the inheritance calculators allow users to play around with Punnett squares and gain a better understanding of simple inheritance patterns.

The curriculum content for Anatomy and Physiology 12 includes “process of DNA replication and effects of DNA mutations” [3]. While Gene Screen doesn’t go into great detail on these topics, the App could be used to review basic concepts in order to prepare for more in-depth learning as well as act as a jumping off point for further investigation into specific genetic diseases.

Suggestions for Lesson Integration While the mini-lessons convey information relevant to the curriculum, I don’t think they would be preferable to a normal lesson on the subject matter (which could be more interactive, in-depth, and flexible than the app). I do, however, believe that the inheritance calculators could be used to augment the lesson on recessive genetic traits/diseases. After discussing inheritance patterns for recessive traits and the associated probabilities, the inheritance calculator could be used by the students to test those probabilities. In pairs, the students could randomly generate ten offspring for a given couple (example: two carriers for a recessive trait) and record their status as unaffected, a carrier, or affected. As a class, you can combine the results from each group to create a

large sample size. The students can then calculate the frequency for each potential offspring and see if they are consistent with the probabilities associated with recessive inheritance.

Gene Screen could also be used as the jumping-off point for a research project. There is a map of genetic diseases included in the app. Users can scroll through a list of diseases and the map will show the global distribution. A button at the bottom of the map provides the user with more information regarding the selected disease. A teacher could ask the students to explore the various diseases included in the app and choose one that strikes there interest. From there a student (or groups) could embark on a research project about their chosen disease.

Concerns When using this app in the classroom, it’s important to make sure you’re not allowing it to create or perpetuate misconceptions for the students. One of the most significant problem areas in Gene Screen is the visual representation of cells and DNA. The cells depicted in the mini-lessons are animated and generalized (similar to those frequently used in textbooks) and do not provide an accurate representation of what cells can and do look like (Figure 4). I think this problem can be mitigated by ensuring that you expose students to pictures of a variety of real cells, and then acknowledge the inaccuracy of the animated cells when you introduce the app.

There is a similar situation with the representation of DNA. When the video zooms into the nucleus of the cell (in the Gene and Inheritance mini-lesson) it shows the DNA arranged neatly in distinct chromosomes (similar to a karyotype) instead of as a disorganized mess (Figure 4). This could lead students to believe that DNA always floats around the nucleus in the condensed form

and that they line up perfectly by size. Once again, I think a teacher could address this problem

by exposing the students to more accurate representations of DNA (for example electron microscope images of a nucleus during interphase and metaphase) before introducing the app to the students.

(Figure 4. The Gene Screen. Left: a screen capture showing the generalized representation of a cell. Right: a screen capture showing the inaccurate representation of DNA in a nucleus.)

Potential App Improvements If I could make improvements to the App, there are a few changes I would make. First of all, I would include some accurate representations of cells and DNA (for example, from electron microscopes). While I don’t think these images should replace the simplified animated versions (which are useful when trying to represent basic principles), they should be acknowledged as the more accurate representation in the mini-lesson.

Conclusions

The Gene Screen App is a pretty average educational tool. While I don’t think the mini-lessons offer any benefits over a teacher-led lesson (in-fact they are probably much less valuable), I do think the inheritance calculators have the potential to augment a lesson plan on inheritance probabilities for recessive traits. I like that the Punnett squares in the app are interactive (allowing students to select the genotypes of the parents), clearly show how each parent contributes one allele to each potential offspring, and then allows the student to press a button that will randomly generate one offspring. I think allowing students to play around with this feature will help them see the probabilities/frequencies of genetic inheritance in action.

Sources

1. Gene Screen. (2015). DNA Learning Centre [mobile application technology]. Retrieved from http://itunes.apple.com

2. BC Curriculum, Science 10: https://curriculum.gov.bc.ca/sites/curriculum.gov.bc.ca/files/pdf/1012/science/en_s_12_aph.pdf

3. BC Curriculum, Anatomy and Physiology 12: https://curriculum.gov.bc.ca/sites/curriculum.gov.bc.ca/files/pdf/10-12/science/en_s_10.pdf...