Manipulating the genome and Gene therapy Flashcards
What is a genome?
Genome is an organisms complete complete set of genetic instruction (the whole nucleotide sequence)
What is genetic engineering? (What are the two tools used for genetic engineering)
Genetic engineering:
select, recombine and introducing/inserting genes from one organism into another, and it does not matter if its a different species.
two tools that are used for geentic engineering: Plasmids and Restriction Enzymes
What are plasmids? Who are they used on? How does it work/how is it used?
Plasmids, circular pieces of DNA that is able to enter and exit the cell membrane of only bacteria cells
Plasmids are circular pieces of DNA that are seperate from chromosomal DNA, therefore they are able to replicate seperatly from chromosonal DNA. and they are expressed seperately.
-> can be passed down between different bacteria genes, and can be associated with antibiotic resistance.
What are restriction enzymes? Who is it used on? How does it work? What is the difference between stickyends and blunt ends? How does this lead into recombinant DNA?
Restriction enzymes are certain enzymes (molecules) that “cut” certain/ specific sequences of the DNA.
-> known was chemical scissors.
1) Scan the DNA and cuts DNA at a specific site (known as the recognition site)
2) Sticky ends are created, cut where it leaves unpaired overhangs, which is used for recombinant DNA.
Same restriction enzyme (cuts the same recognition site) = creation of complementary ends (A bond with T) = can bond with each other
EcoRI = sticky ends (diagonal cut)
Smal = Blunt ends (straight down cut)
What are the two types of DNA?
Coding DNA and non-coding DNA
Coding DNA = region where DNA is expressed
Noncoding DNA = Regions where DNA is not expressed, known as junk DNA, makes up most of the sequence and it is highly repetive.
What is recominant DNA? This is a type of genetic transfer, how is it used?
The combination of 2 different fragments of DNA’s of 2 different organizations/comes from two different sources. (Does not need to be from the same or different species)
All recominant DNA is genetically modied and not naturally present in nature.
-> Can only come from 2 pieces of DNA that is cut with the same restriction enzyme. (Because it creates complementary bonds)
Usage: agricultural benefits
->More crops, disease resistant, crop longevity
What are the prodcuts of genetic engineering/examples of its sucess/usage?
-> Spide silk within goats
(Silk extremely useful because its 5x stronger than steel)
- silk was isolated and inserted in the genomes of goats, which is easier to milk and extract, resulting in the production of mass amounts of silk.
-> BT corn, bacteria that naturally produces petisides, therefore the bacteria is inserted into different foods
- resultsin less pesticide usuage, however can cause more allergies and genetic diversity is lowered.
What is Gene therapy? (What are the two methods it can be corrected by?)
The process of defective genes being corrected by the insertion of a normal gene or the attempt to repair the defective genes.
1) Adding a normal gene
2) Repairing a defective gene
failed gene -> addition of normal DNA -> cell begins to function properly
What is a target cell? What is a vector?
Target cell = the cell with the defective gene
Vector = a medium that carries the normal gene and it is able to take the normal gene into the genome. (Ability to move in and out of the membrane)
How do plasmids work? How do viruses work?
Plasmids are only in bacteria, and it is DNA that is seperate from chromosomal DNA (seperates and replciated different)
CANNOT BE USED IN MAMMELS
Virus is from mammels, and it is a medium that can carry DNA in and out of humans. Different viruses used for different target cells (example: Cold virus for lung cells)
Viruses are a good vector because they are able to infect the cells and transfer the DNA into the target celll.
What is the process of gene therapy? (simple: 3 steps) (general steps: 7 steps)
SImple:
1) Extract the DNA of the Vector (removing the harmful dna)
2) Insert the normal DNA into vector (therefore the normal human DNA is incorperated into the viruses DNA)
3) Insert vector into organism (Numerous viruses are used to infect the target cells as an attempt to insert the normal human DNA into the cells’ genome) (We cannot control where the Virus goes and what it attempts to target, therefore many virus cells are inserted, to increase the chances of sucess)
General
1) cells are harvested from patient
2) Viruses are alted so it cannot reproduce or affect organism harmfully
3) Genes are inserted into virus
4) Altered virus mixed with patient cells.
5) cell is considered transgenic
6) Altered cells injected into patients body
7) Altered cells produce desired proteins
Does gene therapy work?
-> 5 downsides
1) Unhealthy/bad immunse system response
2) Activiations of other cells that can cause leukemia
3) Many treatments (many sessions of gene therapy) repquired for the thing to work because the bad gene can replicated quickly from cell division
4) Bodies must be moniorted constantly
5) Viruses can recover its OWN viral DNA which may cause more harm to the human/diseases
What are the limitations of gene therapy?
1) cannot control where the vector goes when it is inserted into the cells own genome
2) No impact will happen if viruses target a non-coding sequence.
3) If inserted into a coding squence it can disrupt the normal function of the gene
