Application Of Genetic - Genetic Engineering Flashcards
4 types different of forms for genetic engineering
Gene therapy
DNA recombinant
Tissue engineering
GMO
Gene therapy
Insertion of functional gene sequence to counteract non-functional gene to create functional protein
Somatic cell therapy
-targets cells in affected tissue
-not permanent as mitosis replace engineered cell
-cannot be inherited
Germ line therapy
-targets affected gametes (sperm, egg)
-cause permanent changes to embryo
-can be inherited
Ways of delivering gene therapy
Liposomes - gene in lipid vesicle that easily cross cell membrane to DNA
Virus - culture harmless virus to be injected into body with functional gene to change DNA
Problems with Gene Therapy
Use virus - mutate to become pathogenic
Alteration of gene can have effect on other gene - lead to cancer
Baby could not consent and changes are forever
Cystic fibrosis
Protein ‘Cystic fibrosis transmembrane regulator’ does not work due to a gene
Normally allow Cl + sodium to fac. diffuse into trachea
-water potential of mucus decrease = mucus become watery + thin
-cilia can brush away
Mutated =
Protein no work = no ion movement
Water osmosis into cell
Mucus thick + sticky - cannot brush away
Microbes build up
Recombinant DNA
To get a bacteria to create a specific type of protein (insulin)
1)isolation of gene from human for the protein
2)integrate gene into plasmids
3)use a vector to get gene in (bacteria)
4)introduced into host cell
5)cultures modified host cell
Recombinant DNA - isolating target gene
Find a human that has the functional gene for insulin
Recombinant DNA - removal of target gene
Restriction endonuclease enzyme - restriction enzyme that cuts in ‘staggered’ way in DNA
1)gene probe used - locate gene of interest and bind to it
2)restriction endonuclease cut gene of interest in staggered way - exposing the ends of gene of interests called ‘sticky end’ on both sides with exposed bases - usually another gene that was there removed to make room for
Reverse transcriptase enzyme - better than last method since - more gene created compared to 2 from mum + dad + easier to locate + avoid intron
1)reverse transcriptase binds to mRNA of interest and bind complementary bases to form single strand cDNA
2)treated to DNA polymerase to creates double strand DNA
Recombinant DNA - integrate gene into plasmids
1)Plasmids treated to same restriction endonuclease enzyme for target gene - this is to create extra space for gene of interest within DNA of plasmids
2)target gene bind to plasmids DNA
3)DNA ligase added to plasmids to create sugar phosphate backbone for DNA
Plasmids with 2 known antibiotics resistance gene
-outcome: plasmids that took target gene + not taken gene
Recombinant DNA - introduction to vector (bacteria)
Plasmids added to bacteria in suspension
-cold treatment with calcium chloride to improve membrane permeability
-suspension heated for plasmids to get to bacteria (kinetic energy)
Outcome:
Bacteria with no plasmids added
Bacteria with plasmids added but not targets gene
Bacteria with plasmids added with target gene
Replica plating
Use to see which bacteria has plasmids with gene of interest
Plasmids have gene with antibiotic resistance to 2 known antibiotics (A + B)
-known as marker gene
-restriction endonuclease removes gene with antibiotic resistance B
-this allows space for gene of interest to get there
-but process of plasmids having recombinant DNA is low
Culture bacteria with plasmids added on normal agar with labels on different place where colony will form
-once grown transfer bacteria to other 2 agar plate one with drug A other with drug B
-those from original plate that did not appear on both other plate has no plasmids introduced so useless
-those appear on both plate has plasmids but not with target gene - so useless
-those that only appear on original + on drug A has plasmids with target gene - useful and are further cultured
Growing protein
Bacteria with plasmids with right gene are grown and protein produced (insulin) are collected and used
Stem cell + tissue engineering
2 types of stem cell:
-embryonic stem cell in blastocyst - totipotent since can form every cell type
-bone marrow - limited in differentiations
Grow new body on animal then implant on to people
Ethical issue:
-kill potential life
-unexpectedly long term effects
Genetically modified organism
Plants can be modified
-disease resistance - with gene
-resistant to herbicides for weed killer
-delay ripening process - block enzyme that cause plant to expire
Drawback:
Unknown long term effects
Gene leakage - when dead gene not break down properly and get to other not modified plant
Molecular patching
Patch missing exon causing rest of polypeptide chain to not be made
