Cystic Fibrosis DNA Lab

Question 1

What normal gene leads to cystic fibrosis if mutated?

Answer 1

CFTR

Question 2

What does CFTR do?

Answer 2

present in the respiratory system, essential for producing thin, watery mucus

Question 3

What is the most common mutation of cystic fibrosis?

Answer 3

deletion of three nucleotides

Question 4

What happens to those with cystic fibrosis?

Answer 4

experiencing very thick mucus, leads to frequent respiratory infections (pneumonia) and difficulty breathing, greatly reduced life expectancy

Question 5

Compare Individuals with cystic fibrosis to those that are carriers

Answer 5

Individuals with cystic fibrosis inherit two copies of a mutated gene of CFTR, while carriers only inherit one copy

Question 6

How can a baby before birth have their genotype determined?

Answer 6

through DNA testing, Gel electrophoresis

Question 7

Gel electrophoresis

Answer 7

it separates DNA fragments based on size; gel cast out in agarose that contains pores allows DNA fragments to move through gel when an electrical field is created

The electrical field has a positively and negatively charged side; DNA has a negative charge and will be attracted to the positive charge, with smaller fragments of DNA moving quicker and traveling farther

Question 8

Restriction enzyme

Answer 8

enzyme that recognizes specific DNA sequences, cuts DNA it’s set to recognize into two different size fragments

Question 9

How was the restriction enzyme set up in lab?

Answer 9

the non-disease allele contains the sequence recognized by the restriction enzyme, meaning it will be cut into two different sized pieces

the disease allele will not be recognized by the restriction enzyme, meaning it will remain intact or be a larger single piece of DNA

Question 10

How much agarose is needed for gel preparation in lab?

Answer 10

0.23g

Question 11

What is agarose dissolved in? What is is submerged in?

Answer 11

both are done with TAE buffer

Question 12

Note an important step to transferring liquids with a micropipette

Answer 12

using a tip on the end of a micropipette

Question 13

What voltage will be used to run the gel?

Answer 13

125 volts

Question 14

Four steps given in lab to prepare the agarose gel

Answer 14

1. combine 0.23g of agarose with 30ml of TAE buffer
2. heat the solution two consecutive times for thirty seconds, swirling in between
3. allow the solution to cool before pouring into gel tray
4. pour still liguid agarose into the gel tray, insert the comb(to creates chambers) and let the tray sit until it is set

Question 15

Name Steps given for Electrophoresis

Answer 15

1. position the gel in the chamber closest to the negative electrode (anode); they will want to run towards the postive charge (cathode)
2. remove comb to expose wells
3. pipette the sample into each well as indicated from the line of tubes
4. attach the top of the chamber to close off the gel
5. Let gel run for 30-45 minutes at 125 volts
6. remove the gel to sit in Fast blue stain for 5 minutes
7. remove the gel and put into a plastic de-staining container in clear water every 10 minutes until distinct lines can be seen in the gel; then interpret

Question 16

What was the final conclusion of the lab

Answer 16

The baby of Nancy and Jake would be born with cystic fibrosis