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Two Peas in a Pod

A Case of Questionable Twins


Author(s)

Paul Welsh
Science Department
Singapore American School
pwelsh@sas.edu.sg

Abstract

Based on an actual event, this case study focuses on some of the problems associated with reproductive technologies. It tells the story of the "Joneses," who after in vitro fertilization treatment, discover that their fraternal twins are less similar than one would expect two brothers to be. Students work in teams to unravel the mystery using DNA profiling. Related issues that can be explored include the right to medical information, the implications of human error, and racism.


Objectives

  • Review the terms and concepts of fertilization, twinning, fraternal vs. identical twins, in vivo and in vitro fertilization, and DNA profiling.
  • Interpret evidence from several single locus DNA gel electrophoresis tests.
  • Understand the benefits and limitations of reproductive technology.
  • Explore legal and ethical issues implied by the use of reproductive technology.

Keywords

Twins; twinning; fertilization; heteropaternal superfecundation; reproductive technology; in vitro fertilization; IVF; gel electrophoresis; DNA profiling; paternity; maternity; medical error; bioethics; medical ethics

Topical Areas

Ethics, Legal issues, Social justice issues

Educational Level

High school, Undergraduate lower division

Format

PDF

Type / Methods

Interrupted, Role-Play, Trial

Language

English

Subject Headings

Biology (General)  |   Molecular Biology  |   Biotechnology  |  


Date Posted

10/20/03

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Comments


Holly Michels

Health Careers
Wilson Tech
Dix Hills, NY 11746
05/16/2013
I have used the "Two Peas in a Pod" as a case study activity for both a Living Environment Course as well as my Clinical Lab Assisting course. I have had great success using this module and the students really get into it.

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