1. Inherited Diseases Medical Detectives
© 2013 Project Lead The Way, Inc.

2. DO NOW Thursday December 8th
What is the name of gene responsible for HD?
What is the mutation in this gene?
What kind of molecule do genes code for?
How does this mutation result in damage to brain cells?

3. PLAN
Use appropriate laboratory methods to isolate DNA from cheek cells. DO
Discuss Lab
Conduct Lab
Discuss DNA structure and inherited diseases while waiting for DNA to precipitate

4. DNA Isolation Lab Collect Cheek Cells Cell Lysis Precipitate DNA
Initial your 15 mL tube
Swish Gatorade for 1 full minute
Open your tube and spit Gatorade directly into it.
Cell Lysis
Add 2 mL of cell lysis solution
Put the cap back on your tube
Invert tube carefully 5 times
DO NOT SHAKE TUBE
Wait 4 minutes
Precipitate DNA
Hold tube at an angle
Add ice cold ethanol to mL by running it down side of tube
Let sit for 10 minutes in test tube rack
DO NOT MOVE IT

5. What are the FOUR bases found in DNA?
What molecule does DNA code for?
What is the name for the shape of a DNA molecule?
How many chromosomes does a human have?
Why is DNA extraction important?
While you wait…

6. While you wait…
Discussion of Inherited diseases like Huntington’s Disease…..

7. Types of Inherited Diseases
Recessive
Requires a mutated copy of the gene from each parent for child to have the disease.

8. Types of Inherited Diseases
Dominant
Requires a mutated copy of the gene from only one parent for the child to have the disease.

9. Examples of Inherited Diseases
Tay Sachs-recessive (both parents must pass)
Hemophilia-recessive (both parents must pass)
Cystic Fibrosis-recessive (both parents must pass)
Huntington’s Disease-dominant (only one parent must pass)
Polycystic Kidney Disease-dominant (only one parent must pass)
Hemachromatosis-recessive (both parents must pass)
Sickle Cell Anemia-recessive (both parents must pass)

10. Cystic Fibrosis What is it?
A recessive genetic disease caused by the production of abnormal, thick, sticky mucus.
What is the outcome?
Death caused by lung infections usually before age 35.
What are the symptoms?
Coughing and wheezing
Diarrhea
Chronic lung infections

11. Huntington’s Disease What is it?
A dominant genetic disease caused by the deterioration of nerve cells in the brain.
What is the outcome?
Continual decline in mental and physical ability; death usually occurs 15 to 20 years after onset.
What are the symptoms?
Difficulty walking
Uncontrollable body movements
Memory and cognitive impairment

12. What Causes Inherited Diseases?
Genetic material of a cell is changed (called a mutation), causing a change in the cells and ultimately the body’s function which lead to a disease.
The genetic material is deoxyribonucleic acid (DNA) and contains the instructions for the growth and development of the individual.
The changed genetic material is passed from parent to child.

13. While you wait…..
Now answer Conclusion questions 9-11 on page of your biomedical science journal.
If time permits, go ahead and cut the string for your DNA necklace (30 inches long). Tie the ends of the string together to form a loop. Make sure the loop will fit over your head.

14. Making your DNA Necklace
Use a plastic pipet to draw the DNA (white strands) out of the ethanol layer (top layer) in your tube.
Expel the DNA out of the pipet into your pendant tube.
Fill the rest of the tube with ethanol ONE DROP AT A TIME. Do not overfill.
Place your loop of string around the hinge of the cap on your pendant tube and close the cap.
Put on your necklace and invert the tube to watch your DNA move through the ethanol.
ENJOY!!

15. Image Resources
By Français : Domaina [CC-BY-SA-3.0 ( via Wikimedia Commons
By Kashmiri, based on earlier work by Domaina [CC-BY-SA-3.0 ( via Wikimedia Commons
By KES47 (File:Chromosome zh.svg) [CC-BY-3.0 ( via Wikimedia Commons