Lesson 5 — Genetic Code


DNA Fingerprinting

Read pages 649 - 650

The video in the Watch and Listen section of the previous page described the process and uses of DNA fingerprinting. Review the tool of DNA fingerprinting, gel electrophoresis, by reading pages 649 and 650 of your textbook and watching the following excerpt from BiologiX 36 Genetic Engineering: The Science of Manipulating DNA.




 

 

©Alberta Education. Genetic Engineering: The Science of Manipulating DNA (10:08-14:41); Series 36 LearnAlberta.ca

 



Through the video and reading, you should know that DNA fingerprinting has many uses. The most well known use is the identification of criminals in forensics labs. Lesser known uses for DNA fingerprinting are the identification of harmful strains of bacteria, the diagnosis of inherited disorders, the management of wildlife genetic variation, and even the identification of the specific grapes used in a wine. The uses for this technology seem endless.

A significant use of this technology is to help identify relationships among human beings. Given that half the nuclear DNA of a child originates from the mother and the other half is from the father, this information and this technology can be used to identify biological parents.


DNA Fingerprint Analysis Labs

  1. Read the Thought Lab titled "Reading a DNA Fingerprint" on page 651. Answer the Analysis Questions to test your knowledge of DNA fingerprinting. Check your answers with the solutions linked below.

    2. Self-Check Answers


    1. The parents of the child are Parents B. They are the only parents that have DNA segments the same as the child has.

    2. Five of the child's DNA segments (50 percent) match the mother, and the other five (50 percent) match the father.

    3. Other situations where DNA fingerprinting may be useful are in paternity cases, in identifying the remains of murder or accident victims, in tracing the movement of wildlife, or in plant and animal breeding programs.


  2. Your DNA makes you 'YOU'.  No two individuals have the same DNA unless they are identical twins, triplets, etc. In this simulation, you will look at the DNA fingerprints of frogs. You will use the DNA fingerprints to identify twin frogs and investigate the relationship between DNA fingerprints and frog traits. Open the  DNA Fingerprint Analysis Gizmo.

    Problem
    How can identical twins and physical characteristics be identified using DNA fingerprints?
    Procedure
    Follow each step in the Exploration Guide in the DNA fingerprint analysis gizmo.


Self-Check

  1. Why is your mitochondrial DNA identical to the mitochondrial DNA of your mother rather than to that of your father?

  2. Give two examples of ways that the study of DNA sequences can help scientists learn about genetic relationships, genetic variations, or evolution.

  3. What was the objective of the Human Genome Project?

Self-Check Answers


  1. Your mitochondrial DNA is identical to the mitochondrial DNA of your mother because your father's sperm contributed essentially no cytoplasm and ,therefore, no cytoplasmic organelles to its offspring. On the other hand, your mother's egg provided most of the cytoplasm and cytoplasmic organelles, including the mitochondria. Although the DNA in the nuclei of your cells is made of an equal combination of DNA from your mother and your father, your mtDNA came from the cytoplasm of your mother's ovum.

  2. DNA allows scientists to study genetic variations among individuals of the same species as well as genetic variations between different species. This helps scientists to track the evolution of a species through time. Comparing the DNA of ancient plants, animals, and even bacteria with the DNA of their modern counterparts can reveal such varied information as the ancestry of modern organisms, the movement of populations through time, the evolution of particular disease-causing bacteria, and the way that ecosystems respond to climate change.

  3. The objective of Human Genome Project was to determine the sequence of nitrogen bases for the DNA in the chromosomes of the entire human genome. The Human Genome Project is an important step in understanding how genes determine our genetic characteristics. This understanding can be applied to medical genetics and the treatment of disease as well as to other sciences.

Going Beyond

Hypothesize as to how Y-chromosomes could be used to trace ancestry. Would you be tracing maternal or paternal ancestry using this chromosome?

Biology 30 © 2008  Alberta Education & its Collaborative Partners ~ Updated by ADLC 2019