The Hunt for mtDNA

 

Introduction – Task – Process – Evaluation - Conclusion

 

Introduction

· Congratulations!  You have just been hired on as a forensic scientist to help solve a long-standing missing persons case.  Just days ago an anthropologist found human bones at a site in South Africa.  Investigators think they might belong to a Nobel Prize-winning dung beetle biologist who disappeared near this location in South Africa. Since the bones have been exposed to severe weather for many years, the only DNA that may be salvageable is mtDNA. 

Task

· Your job as the Chief Forensic Scientist is to find out if these are, in fact, the remains of the late African dung beetle Biologist. 

 

· You must find relatives who can be used as a match, or to prove that these bones are from their deceased relative.

 

· The catch: Only some relatives can provide a match for the mtDNA.

 

· Your job: Find out which relatives can be used as a match for the mtDNA.

 

Process

· First: Research the inheritance pattern of mtDNA in order to find out which relatives can be used as a match.  Your answers are on the following page:

Ř What is the mtDNA?

Ř How is it inherited?

 

· Second: Investigators have created a pedigree chart (which is also located in your lab manual) to help you find living relatives to the missing dung beetle biologist.  Use this chart to trace the ancestry of the mtDNA in the missing person’s lineage.  In order to learn more about pedigree charts, and how to use them, consult the following webpage:

Ř What is a pedigree chart?

 

Geneology chart

 

 

· Third: Once you solve the puzzle of which living relatives can be used for the mtDNA draw in red pencil on your pedigree chart.  Trace the mtDNA on the pedigree chart by using the red pencil.  Then fill in the circle or square for the living relatives that can be used. 

 

· Finally: Write a one-paragraph justification for why particular relatives have been chosen to serve as proof.  Answer the following questions within the paragraph:

o    Would the relative’s mtDNA look exactly the same, or just similar?

o    How would using the relative’s mtDNA help to solve the missing person’s case?

 

Additional Resources

· Consult the following additional resources to answer your questions:

o    The FBI link to solving crimes using the mtDNA.

o    Read this National Geographic article about Neanderthals, humans, and the mtDNA.

o    Learn more detail about mtDNA.

 

Evaluation

· The following Rubric will be used to evaluate your performance:

 

 

Rubric: The Hunt for mtDNA

 

 

Excellent

Good

Fair

Minimal

Comments

Pedigree Chart

  • Student properly traced the lineage of the mtDNA
  • Student properly identified the living relatives that can be used for the mtDNA

5

4

3

2

 

Justification

  • Student thoroughly answered the following question, “Would the relative’s mtDNA look exactly the same, or just similar?”
  • Student thoroughly answered the following question, “How would using the relative’s mtDNA help to solve the missing person’s case?”
  • Paragraph was well written with few grammatical errors.

5

4

3

2

 

 

Overall Comments:                                                     Total Points: ­­__ /__

 

Conclusion

· This webquest should have helped you to learn about the mitochondrial DNA (mtDNA).  You should be familiar with the pattern of inheritance of mtDNA. 

· Let me ask you a question:

 

 

 

 Who would have the same mtDNA in your family?

 

Sources

  • This webquest is based off of a lesson titled, “The Last Flight of Bomber 31” from www.pbs.org.