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					Genetic Science Ethics – Circle time

(Pick as many scenarios that you would like to discuss with the group. Students also have the
option of picking scenarios for the class discussion as well.)

1. You've found out that the child you (or your wife) carries has the gene for dwarfism. A new
therapy exists that may repair this gene before the child is born. What do you do?
a. Allow the child to be born with the gene, and we will accept the child as is.
b. Attempt the new therapy to repair the gene
c. Terminate pregnancy.

2. An agricultural company has found a way to make tomatoes 50% larger by splicing elephant
genes into the tomatoes. Will you:
a. Buy the tomatoes and have no problem eating them
b. Probably not buy or eat the tomatoes
c. Protest the company. It's not right to fool with mother nature!


3. Pet cloning is now available at the local mall. You used to have a pet dog named Charlie, but
he died two years ago. Now you learn that you can get a new Charlie by just bringing in a sample
of his hair. What do you do?
a. Find a strand of Charlie's hair as soon as possible. Can't wait to see Charlie again!
b. Let sleeping dogs lie. (Don't clone Charlie)


4. A company can now create test tube babies according to parent specifications. The company
can make sure that your child has all the traits you desire - hair color, intelligence, athletic
ability, etc….. What do you do?
a. Sign me up, I want my child to be perfect.
b. I'd rather let nature take its course.
c. We might adjust some things to make sure the child is healthy (and has no genetic
abnormalities).

5. You find out that you and your wife are both carriers for a gene that could cause your children
to be severely disabled. Your child has a 25% chance of developing this condition. What do you
do?
a. Choose not to have children, better to adopt than risk it.
b. Those aren't bad odds, we'd take the chance.


6. Your family is known to have Huntington's disease. Huntington's is a
disease that causes its victims to slowly lose their ability to speak, walk and
function. Ultimately, Huntington's causes death. The symptoms do not usually
appear until the person is in their forties. There is a test that will tell you
whether you have the gene for Huntington's disease. What do you do?
a. I would take the test, so that I would be better prepared for the future, and
could make sure my family was taken care of.
b. I would not want to know.

7. Cloning technology is perfected. A clone can be made from adult tissue samples. You learn
that you need a kidney transplant, but there are no donors available. A doctor suggests that you
make a clone of yourself, so that the kidney would be a perfect match. What do you do?
a. One is enough of me, I'll wait for a donor.
b. Clone myself, two is better than one.


8. A government organization is proposing to have all citizens of the US submit a sample of their
hair so that their DNA can be scanned and kept on file. Each person's DNA would be kept in a
national database so that police could access the DNA when a crime was committed. Do you?
a. Support this legislation
b. Oppose this legislation
c. Suggest the legislation be modified, only people with criminal records should be scanned.


9. An experimental procedure would allow you to add genes to your
body. You can order certain genes, like a smart gene, or an athletic
gene, or a musical ability gene. What do you do?
a. We would have the procedure done, I'd like to be better in school
and at sports.
b. We would not have the procedure done, people should accept
themselves the way they are


10. An insurance company is requiring individuals to get genetic
testing performed to determine whether they have a higher risk of
heart disease, cancer, or other diseases. They are requiring that all
people wanting health insurance be tested. What do you do?
a. find another insurance company, that information is none of their business
b. submit my DNA for a test, I'd like to know anyway.
UAGC-Living Environment

Name:__________________________ Date:_______________ Module:__________

LT: I can use amino acid sequences of organisms in order to assess their traits.

DNA, RNA, and Snorks

Introduction: In this simulation, you will examine the DNA sequence of a fictitious organism -
the Snork. Snorks were discovered on the planet Dee Enae in a distant solar system. Snorks only
have one chromosome with eight genes on it. Your job is to analyze the genes of its DNA and
determine what traits the organism has and then sketch the organism (You can be creative here).

For simplicity, the gene sequences are much smaller than -real- gene sequences found in living
organisms. Each gene has two versions that result in a different trait being expressed in the
snork.

Genes                         Amino Acid Sequence                     Description
Gene 1 - body covering        val - ser - leu                         hairless
                              val - ser - lys                         hairy
Gene 2 - body style           tyr - pro - glu - glu - lys             plump
                              val - pro - thr - glu - lys             skinny
Gene 3 - legs                 leu - leu - leu - pro                   3 legged
                              leu - leu - ser - ala                   2 legged
Gene 4 - head shape           ala - val - val                         round head
                              val - ala - ala                         square head
Gene 5 - tails                his - ile                               tail
                              his - his                               no tail
Gene 6 - body pigment         ser - pro - val                         blue pigment (hair/skin)
                              val - phe - tyr                         red pigment (hair/skin)
Gene 7 - eyes                 asp - ile - leu - leu - pro - thre      small slanted eyes
                              asp - ile - pro - pro - pro - thre      large round eyes
Gene 8 - mouth                val - asp - asp - ala                   circular mouth
                              asp - asp - asp - ala                   rectangular mouth
Gene 9 - ears                 phe - ser - gly                         pointed standing-up ears
                              phe - phe - gly                         rounded floppy ears
Gene 10 - arms                arg - tyr - cys - lys                  long spaghetti like arms
                              arg - arg - asp - thre                 short stumpy arms

Each of the following DNA samples was taken from volunteer snorks. The DNA was then
transcribed to its complimentary RNA strand. Your job is to analyze the RNA sample and
determine the phenotype (how the organism looks) based on the sequence. Remember that AUG
is a start codon, and it signifies the beginning of each gene. UAA is a stop codon and signifies
the end of a gene. The genes are in order from gene 1 to gene 9. Your teacher may assign you
one or all of the samples to analyze. Use the codon chart from yesterday’s DNA packet, or view
one on the web.

Snicker Snork

AUG | GUC AGC AAA | UAC CCC GAA GAG AAA | CUC UUA AGU GCG | GCU GUU
GUG | CAU CAU | GUU UUU UAC |

| GAU AUC UUA CUG CCC ACC | GAC GAC GAU GCC | UUU UCU GGG | AGA UAU
UGU | UAA

Snuffle Snork

AUG | GUA UCU AAA | GUU CCU ACU GAA AAG | CUU CUC CUC CCC | GUU GCG
GCU | CAU CAC |

| GUA UUU UAU | GUA AUU CUU CUG CCC ACA | GUU GAC GAC GCA | UUC UCG
GGU | AGA UAU UGU | UAA

Snapple Snork

AUG | GUC AGC CUU | GUU CCC ACA GAA AAA | CUC UUA AGU GCG | GUU GCG
GCU | CAC AUU |

| UCU CCC GUA | GAU AUU CCC CCC CCC ACC | GAU GAC GAC GCA | UUC UUU
GGG | CGC CGG GAC | UAA

Snoopy Snork

AUG | GUA UCC CUC | UAC CCC GAG GAA AAA | UUA UUA CUG CCC | GCU GUU
GUA | CAU AUU |

| UCU CCC GUA | GAU AUU CUU CUG CCC ACA | GUU GAU GAU GCC | UUU UCU
GGU | CGC CGU GAC | UAA
Use the space below to draw your Snorks
How DNA Controls the Workings of the Cell

LT: l can demonstrate how DNA controls the workings of a cell

                      Below are two partial sequences of DNA bases (shown for only
                      one strand of DNA) Sequence 1 is from a human and sequence
                      2 is from a cow. In both humans and cows, this sequence is part
                      of a set of instructions for controlling a bodily function. In this
                      case, the sequence contains the gene to make the protein
                      insulin. Insulin is necessary for the uptake of sugar from the
                      blood. Without insulin, a person cannot use digest sugars the
                      same way others can, and they have a disease called diabetes.

                      Instructions:

1 Using the DNA sequence, make a complimentary RNA strand from both the human
and the cow. Write the RNA directly below the DNA strand (remember to substitute U's
for T's in RNA)

2. Use the codon table in your book to determine what amino acids are assembled to
make the insulin protein in both the cow and the human. Write your amino acid chain
directly below the RNA sequence.

Sequence 1 - Human

C C A T A G C A C G T T A C A A C G T G A A G G T A A

RNA :

Amino Acids:

Sequence 2 - Cow

C C G T A G C A T G T T A C A A C G C G A A G G C A C

RNA:

Amino Acids:

Analysis

1. Comparing the human gene to the cow gene, how many of the codons are exactly
the same? ___________

2. How many of the amino acids in the sequence are exactly the same? ________
3. Could two humans (or two cows) have some differences in their DNA sequences for
insulin, yet still make the exact same insulin proteins? Explain.

4. Find ALL of the codons that can code for the amino acid leucine and list them.

5. Diabetes is a disease characterized by the inability to break down sugars. Often a
person with diabetes has a defective DNA sequence that codes for the making of the
insulin protein.

Suppose a person has a mutation in their DNA and the first triplet for the insulin gene
reads T A T.


The normal gene reads T A G. What amino acid does the mutant DNA and the normal
DNA code for and will the person with this mutation be diabetic?

6. Another mutation changes the insulin gene to read T C T (instead of the normal

T A G). Will this person be diabetic? Explain.

7. DNA sequences are often used to determine relationships between organisms. DNA
sequences that code for a particularly gen can vary, though organisms that are closely
related will have very similar sequences. This table shows the amino acid sequences of
4 organisms.

Human:    CCA      TAG     CAC     CTA           Chimpanzee:      CCA    TAA   CAC    CTA


Pig:   CCA     TGT     AAA     CGA               Cricket:   CCT    AAA    GGG     ACG


Based on these sequences, which two organisms are most closely related?
________________________

8. An unknown organism is found in the forest and the gene is sequenced as follows:

Unknown: C C A T G G A A T C G A

What kind of an animal do you think this is? _______________________________
Bacterial ID Lab at Howard Hughes Medical Institute

LT: I can extract and isolate DNA from
unknown bacteria

http://www.hhmi.org/biointeractive/vlabs/index.html

www.hhmi.org >> resources & publications >> students >>
biointeractive >> virtual labs > "The Bacterial Identification Lab"

The procedures necessary for extracting and isolating DNA of an
unknown bacteria are costly, time consuming, and can even be
dangerous in that it can expose a lab technician to pathogens.
Fortunately, technology has given us virtual labs that will show
how these procedures are done without the mess and the fuss. In this internet activity, you will
use a virtual lab to perform the following procedures:

      Prepare a sample from a patient and isolate whole bacterial DNA.
      Make many copies of the desired piece of DNA.
      Sequence the DNA.
      Analyze the sequence and identify the bacteria

Learning Objectives

      What kind of patient samples are used for the purpose of identifying possible pathogens?
      What does PCR do, how does it work, and why is it useful?
      How do you separate the desired DNA from all others?
      How does an automatic DNA sequencer work?
      Why is it possible to use a DNA sequence to identify bacteria?

Instructions: The virtual lab is divided into six sections that walk you through the procedures
involved. Don't forget to read the notebook section as well, which has further explanation about
what you are doing and why. As you complete each section, answer the corresponding questions.

Sample Prep

   1. The first step in the extraction process uses a wire loop to do what?

       2. Why are the digestive enzymes necessary for DNA extraction?


       3. The centrifuge separates the cellular content into two distinct layers. Describe these
       layers and what is contained within them.
PCR Amplification

4. PCR stands for __________________________________

5. What is a primer?

6. Describe what happens during the 3 cycles

Melt



Anneal



Extend



7. After 30 cycles, how many copies of the initial DNA strand have been produced?
Why is this stage called "amplification"?



PCR Purification

8. To confirm that the PCR worked, three lanes are run that contain 3 materials. What materials
are in the 3 lanes?

Lane 1 ______________________ Lane 2 __________________ Lane 3 ___________________

9. What is the overall purpose of the purification stage?



Sequencing Prep

10. Describe the “sequencing brew” that you added your purified PCR to.



11. The purpose of the second PCR is not to create identical copies like the first PCR you ran.
What is the purpose of this PCR?
DNA Sequencing

12. What is the final PCR product, the stuff contained in your 12 tubes?



13. What is gel electrophoresis?



Sequence Analysis

14. What is BLAST?

15. What is the identity of the bacteria in your sample? Follow the steps listed on the page and be
patient. BLAST data can take a while to search.

Extension and Formative Assessment

**Look at the learning objectives at the beginning of this sheet. Did you accomplish these
objectives? Redo the simulation to reinforce the steps involved.

				
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