Genetics is an Important Factor in Addiction
Go to the following LINK
This is part of the University of Utah’s website Learn.Gentics
Go to the link “PI: Pedigree Investigator, On the Case of Nicotine Addiction”
Read the direction then click “Play”
Click on the drop down menu for “What is it”
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1. How do we denote that a risk factor is present in the individual?
2. Name 4 risk factors for nicotine addiction.
ADHD, 2. depression, 3. spending a lot of time w/ people who smoke, 4. tendency toward risky behavior
Click on the drop down menu for “Why do it” and read the slide show
3. Why do scientists have to study multiple families in order to study traits like addiction?
Genes vary from family to family
Play the video clips and complete the pedigree.
4. Complete the pedigree and show it to Mr. Foster for points.
Click the back button and return to the page titled “Genetics is an Important Factor in Addiction”
Click on the link “The Gene Discovery Process”
Answer the following questions (5-7) while going through slides (1-9). Turn narrator off/on if you want.
5. Nicotine works by binding to nicotinic acetylcholine receptors (nAChRs).
6. The 8 subunits of nAChR present in the brain are encoded by 8 different genes.
7. Past genetic studies have shown a link between the CHRNA4 gene and nicotine addiction, as well as
Attention Deficit Hyperactivity Disorder (ADHD).
Putting our Heads together:
8. What 3 researchers collaborate to provide part of the puzzle for addiction studies?
Protein biochemist, Clinician, DNA Analyst,
9. Go through slides 1-5 and explain how genes translate to addiction.
Gene  protein  response to nicotine  addiction or not
Why Isn’t It 100%:
10. Which allele is very common between nicotine addicts and ADHD? 2
Go to the following website:
http://learn.genetics.utah.edu/units/addiction/index.cfm
Read thoroughly as you navigate through this website.
Follow the link, “Natural Reward Pathways Exist in the Brain”
11. Make a rough sketch of a neuron and label it as it is on this page with the 7 labels.
Dendrite
s
Nucleus
Axon Terminals
Cell Body
Axon
Nodes of Ranvier
Myelin Sheath
12. Define Neuron: Neurons are the cells responsible for passing chemical and electrical signals along the
pathways of the brain and Nervous System
Click through the slide show about how “The Reward Pathways Reinforce Behavior”.
13. What is the central job of the reward pathway? driving our feelings of motivation, reward and behavior make
us feel good when we engage in behaviors that are necessary for our survival
14. The release of what chemical in the brain gives you a “little jolt of pleasure”? Dopamine
15. The reward pathway connects two regions of the brain that are responsible
for_behavior_____and__memory________.
Neurons communicate via the synapse
16. Define synapse: Information from one neuron flows to another neuron across a small gap called a synapse
Click the “Back” button and return to the page titled “The New Science of Addiction: Genetics and the Brain”.
Follow the link, “Drugs alter the Brain’s Reward Pathway”.
17. Which part of the brain do drugs cause dramatic changes in? synapses in the brain
18. Explain why drug users develop a “tolerance” reduce the number of dopamine receptors
19. The faster a drug is delivered to the system the _more likely it will become addicting________.
Look at the PET scan of a brain belonging to a previous cocaine user.
20. Do the affects on the brain from cocaine go away very quickly? No, >100 days
Click the “Back” button and return to the page titled “The New Science of Addiction: Genetics and the Brain”.
Follow the link, “Genetics is an Important Factor in Addiction”
21. What are scientists looking for when they look for “addiction genes”? biological differences that may make
someone more or less vulnerable to addiction
22. Explain the difference between vulnerable and inevitable. (According to Dr. Hanson-Listen)Vary
23. Explain what part of addiction is probably determined by genetics. (Listen to Dr. Hanson) Vary
24. The _A1_allele in the dopamine receptor gene __DRD2_ is more common in people addicted to cocaine or
alcohol.
25. Non-smokers are more likely than smokers to carry a protective gene, _CYP2A6_________, which causes them to
feel more nausea and dizziness from smoking.
26. Alcoholism is rare in people with two copies of the __ALDH*2 ___________ gene variation.
Click on “Learn more about using mice to study addiction”.
27. How does selectively breeding mice teach us about genetics of addiction? Addictive behaviors passed on
28. Name 4 other animals that can be used to study genetics of addiction. Chimp, Zebrafish, Fruitfly, Roundworm
Click the “Back” button and return to the page titled “Genetics is an important factor in addiction”.
29. How can drugs be used to help addicts? researchers can focus on one gene product and develop a drug that
modifies its activity