DNA Technology And Genetic Engineering

Question 1

DNA sequencing reveals structure of DNA?

Answer 1

Yes, prior to sequencing DNA must be amplified to get adequate amount.

Question 2

Primers

Answer 2

Enable initiation of DNA synthesis

Question 3

DNA polymerase

Answer 3

Replicates the DNA

Question 4

Gel electrophoresis

Answer 4

Separates DNA strands by size

Question 5

Nucleotides

Answer 5

A , G , C , T

Question 6

Recombinant DNA Technology —

Answer 6

— Isolating and cloning genes

Question 7

Recombinant DNA

Answer 7

— cutting, splicing, and coping DNA

Question 8

Tools for manipulating DNA

Answer 8

— Restriction enzymes
— DNA ligases
— Plasmids

Question 9

Restriction enzymes

Answer 9

Cut DNA at specific sites, often palindromes.

Question 10

DNA ligases

Answer 10

Join fragments of DNA

Question 11

Plasmids

Answer 11

Small circular pieces of DNA to which desired genes can be added and inserted into bacteria for amplification.

Question 12

What is the basic idea behind genetic engineering?

Answer 12

The basic idea behind genetic engineering is to join DNA from two or more sources.

Question 13

What does The Polymerase Chain Reaction forms part of?

Answer 13

Cloning DNA Fragments

Question 14

Cloning DNA Fragments: The polymerase chain reaction

Answer 14

— used to rapidly amplify DNA sequences to obtain millions of copies;

*DNA to be amplified, primers, hear-stable DNA polymerase are combined.
*Repeated heating and cooling cycles allow for rapid amplification of a sequence of DNA defined by the primers.

Question 15

Identifying the source f DNA: DNA Fingerprinting

Answer 15

• Often DNA sample must be amplified by PCR first.
• DNA is cut with restriction enzymes
• Different individuals will have different lengths of DNA between the restriction sites.
• DNA is separated by gel electrophoresis and fragment patterns is compared.

Question 16

What kind of Transgenic Bactria have been developedI?

Answer 16

• Insulin
• Human growth hormone
• Erythropoietin
• Tissue plasminogen activator (tPA)
• Factor VIII (blood clotting factor needed by many haemophiliacs)
• Vaccines

Question 17

What does Genetic Engineering Creates?

Answer 17

Transgenic Organisms (eg. Insulin, human growth hormone, etc).

Question 18

Transgenic Plants

Answer 18

Are more vitamins and pest resistance.

Question 19

Transgenic plants have been modified to express what kind of things?

Answer 19

• Increased resistance to freezing
• Longer shelf life
• Increased vitamin A
• Edible vaccines
• Human proteins (i.e., albumin)
• Increased resistance to pests

Question 20

Bigger challenges related to Transgenic Animals?

Answer 20

• More difficult to introduce foreign DNA into animal cells.
• Cloning more difficult.

Question 21

What are some successes in Transgenic Animals?

Answer 21

• Bovine growth hormone (bGH)
• Gene pharming

Question 22

Bovine Growth Hormone (bGH)

Answer 22

Used to promote faster animal growth.

Question 23

Gene pharming

Answer 23

Introducing human genes into rarity animals in such a way that the human protein is produced in the dairy animal’s milk.

Question 24

Gene therapy

Answer 24

Introduction of human genes into human cells to treat or correct disease.
(For example, for ADA into patient’s T cells and reintroduce the genetically modified T cells into the patient).

Question 25

Obstacles of gene therapy?

Answer 25

• Difficult to introduce genes into the “right” cells, where the genes would normally be expressed.
• Need effective means of delivering genes.
• Can corrective genes be introduced into reproductive cells to stop the passing of defective genes to offspring?

Question 26

Retroviruses

Answer 26

• Human genes can be packaged in retroviruses, which can be introduce genes into human cells.
• Problems with retro viral vectors is that will only insert genes into dividing cells and insertion sited are random.

Question 27

How can vectors transfer genes to human cells?

Answer 27

• Retroviruses
• Liposomes
• Injection naked DNA
  All of these methods are experimental.

Question 28

Severe combined immunodeficiency (SCID)

Answer 28

• Inherited disorder, lack an enzyme, adenosine deaminase (ADA)
• Deficiency of B and T cells
• Highly susceptible to infections

Question 29

Cystic fibrosis

Answer 29

Experimentally delivering the “normal” gene in a viral vector to the recipient in a nasal spray.
*results are slightly encouraging.

Question 30

Cancer

Answer 30

• Add genes for interleukins into cancer cells
• Incorporate gene for a foreign protein into cancer cells
• Insert genes for proteins that initiated apoptosis into cancer cells