19 Flashcards
I’ll
Oioin
Type one diabetes - Frequency- onset
1:5000
- childhood onset (mostly)
- autoimmune - body attacks B cells in pancreas thus can’t produce insulin
Both types if diabetes have
Genetic components to them
Type 2 diabetes
- 15% lifelong risk
- lifestyle/ environment
Diagram of type 1 diabetes
Progression of gene therapy knowledge in 1960
1922: insulin first isolated from pig and cattle
1950s: identified protein sequences/structure
- treatment for diabetes was purified insulin for pigs and cattle
Consequences (and why) of insulin purified from pancreas of cattle or pigs
- human amino acid sequence is similar but not identical
- immune responses range from local irritation to anaphylactic shock
- not always pure
(Cow insulin has 2 amino acid changes in alpha chain surrounding the disulphides bond, pig insulin has one extra amino acid at the C terminal of the peptide chain - the 3 amino acid changes in cow and one in pig at great enough to induce immune response if injected into human)
Therapeutic proteins - human sources being used - pathogen transmission
- issues around safety (pathogen transmission), yield and source of protein (tissue availability)
- factors collected for haemophilic patients ending up containing HIV or hepatitis - couldn’t screen for HIV- many hemphouliacs ended up with aids
- growth hormone collected from cadavas used for dwarfism (need many pituitary glands to treat a single patient increasing risk every time you take a sample) this transmitted prion proteins - mad cow disease - Jacob
Profession in gene therapy up to 2010
1922: insulin first isolated from pig and cattle
1950: insulin protein sequence ‘ structure identified
1973: recombinant DNA technology born
1977: insulin gene mapped too chromosome 11
1980: gene for insulin sequenced
1982: Eli Lilly produced the first recombinant insulin
What are recombinant DNA technologies
Joining bits of DNA together (sometimes form different species). These are inserted onto an organisms to produce (express) a useful protein.
(E.g : Aequorea Victoria - GFP - produced fluorescent glow in stress response - can be inserted into other animals
- beta barrel structure )
Plasmids are critical elements for…
… recombinant DNA technologies
What are plasmids
- (usually) circular pieces of double stranded DNA
- replicate independently of the hosts chromosomal DNA
Where are plasmids found
- common in bacteria
- also found in eukaryotes
What do plasmids provide?
-provide a benefit to hosts EG antibiotic resistance
Key components of recombinant DNA plasmids
- origin of replication
- antibiotic resistance
- promotor