Use of DNA technologies Flashcards
(16 cards)
USE OF RECOMBINANT TECHNOLOGY
What is the use of recombinant technology in medicine?
- This can be used to produce human proteins. For example, bacteria can be used to make human insulin to treat Type 1 diabetes and Antibodies and antigens can be placed on vaccines.
- Gene therapy.
What is the use of recombinant technology in industry?
Transgenic bacteria can make enzymes that are used in industrial processes and food production.
What is the use of recombinant technology in agriculture?
- Crops can be genetically modified to have pest and disease resistance, higher yield or drought tolerance.
- Mammals can be genetically modified to have a higher meat or milk yield.
What is gene therapy used for? How does gene therapy work?
- To modify the mutated alleles in people with genetic disorders and treat illness.
- DNA is inserted into the patient’s DNA using a vector, like a plasmid or virus. The inserted DNA can either silence the faulty allele or it can insert a healthy allele.
What are the downsides of using gene therapy to treat illness?
Altering the alleles in somatic cells will not cause heritable changes meaning that the patient’s children could still inherit the faulty allele that causes disease.
What are the benefits of using recombinant technology?
- The treatment of genetic disorders using transgenic bacteria and gene therapy could save or improve the quality of life.
- The use of recombinant technology to produce enzymes for food production and industrial processes could prevent animals from being killed to obtain those enzymes.
- Genetically modifying crops to be drought-tolerant, pest-resistant and disease-resistant could reduce famine in areas that have harsh living conditions.
What are the downsides of using recombinant technology?
- There is a risk of transferring antibiotic-resistant genes to pathogenic bacteria.
- Genetically modifying animals to increase meat and milk yield could decrease their quality of life.
GEL ELECTROPHORESIS
What is gel electrophoresis used for?
Used to separate DNA fragments based on their length.
Describe the process of gel electrophoresis.
- DNA fragments are loaded onto a plate containing agarose gel and a potential difference is applied for a short time.
- DNA fragments are negatively charged, so when a potential difference is applied, they will move towards the positive electrode.
- Shorter DNA fragments will move faster, so they will travel further along the plate in the given time.
- A DNA ladder can be run on the side to see the length of the DNA fragments.
- The DNA can be visualised under UV light if a fluorescent light is attached to the DNA.
What is a DNA ladder?
It contains DNA fragments of known length to compare the positions of the DNA fragments on the plate to.
DNA PROBES AND DNA HYBRIDISATION
What are DNA probes and what are they used for?
They are short, single strands of DNA which have a complementary base sequence to a specific allele. They are used to locate specific alleles of genes in the DNA of an organism.
Describe how the DNA of the sample is treated and how DNA probes are used to locate a specific allele on the DNA?
- The DNA is extracted from the cells of the sample.
- Restriction endonucleases are used to hydrolise the DNA into fragments.
- The DNA fragments are amplified using the polymerase chain reaction.
- The DNA fragments are separated using gel electrophoresis.
- The DNA fragments are treated to be single-stranded and expose the bases.
- The specifically-marked DNA probes will hybridise with the specific allele if it is present in the DNA.
- Then the gel is visualised to see of the probe is present. Using UV light if there is a fluorescent marker and autoradiography if there is a radioactive marker.
What are the uses of DNA probes?
- It allows people to see if they carry the recessive allele that is responsible for a certain condition. They can then use this to see if they are at higher risk of having certain diseases or weigh out the risk of passing on genetic disorders to their children.
- It allows genetic screening for alleles that affect how well a person responds to certain drugs and helps doctors choose the drugs that best suit the patient’s needs.
