Gene therapy, synthetic hormones

What is gene therapy?

Aims to treat or cure genetic abnormalities by identifying faulty genes and inserting healthy ones

What is the aim of gene therapy?

Gene therapy aims to treat or cure genetic abnormalities by identifying faulty genes and inserting healthy ones
It is only useful for monogenetic/single gene disorders (a disorder that affects only one gene)

What does gene therapy use?

Uses gene technology for the same technique, with the same non-faulty gene being inserted in a vector, a carrier which transfers the DNA into the patient's cell (transfection)
The vector is introduced into a sample of patient's cell

Where is gene therapy research concentrating around?

Single-gene disorders like:
-Cystic fibrosis
-Huntington's disease
-Muscular dystrophy
-Sickle-cell anemia
-Curing type 1 diabetes
The goal is to correct the underlying cause

What are some areas of possibility for gene therapy?

-Replacing a mutated gene with a healthy copy
-Fixing or inactivating mutated genes
-Inserting a new gene that will fight the disease
-Making immune system recognise diseased cells

What is the concept of gene therapy?

Using a vector to deleiver a desired DNA into a cell. This DNA can be incorporated into the cell's nucelus and undergo transcription and translation to produced the desired protein.

What does gene therapy have a limited sucess rate?

Gene therapy often has a low success rate because it's hard to get the new gene into the right cells, and even when it does work, it can cause serious or even life-threatening side effects (e.g. gene ends up in wrong place in DNA and can trigegr immune reactions)

What gene therapy has some success?

SCID (affects immune system)

What are the steps in gene therapy?

1. Modified DNA is inserted into vector
2. Viral vector containing corrected DNA is introduced to a cell culture (cultured to amplify the correct gene)
   Cytoplasm:
3. Virus is taken in by the cell and packaged in vesicle
4. Virus makes it ways to the cell nucleus where vesicle breaks down releasing vector
   Nucleus:
5. Correct DNA is integrated with patients DNA
   Cytoplasm:
6. Encoded protein produced by the cell

What is somatic gene editing?

Somatic gene editing involves modifying the DNA in non-reproductive cells (somatic cells) to treat or prevent diseases. These changes are not passed down to future generations, unlike germline editing.

What is germline gene editing?

Germline gene editing involves altering the DNA in a person's egg, sperm, or early embryo, with the aim of making changes that can be inherited by future generations.

Compare somatic and germline gene editing (edit, copy, risks).

Edit:
Somatic: Target genes in specific type of cells (e.g. blood cells)
Germline: Made early in development so any change is copied into all of the new cells (inherited)
Copy:
Somatic: The edited gene is contained only in the target cell type. No other type of cells are affected
Germline: The eduted gene is copied in every cell including sperm or eggs
Risks:
Somatic: Any changes, including potential off-target effects are limited to the treated individual
Germline: Off target effects and then passed down to children

Compare somatic and germline gene editng (next generation, consensus)

Somatic: The edited gene is not passed down to future generation
Germline: Edited gene is passed down on to future generation
Consensus:
Somatic: Somatic cell therapies have been researched for more than 30 years and high regulated
Germline: New so has new legal and societal considerations

How can gene therapy be used to help treat type 1 diabates?

Repogramming other cells to produce insulin (cells other then the beta cells in the islets of Langerhans in the pancreas).

What is an example of gene therapy in diabetes (the methods)?

-Gene for insulin introduced into a vector
-The vector is then used to infect the desired cells such as alpha cells in he islets of Langerhans (beta cells are being destroyed so alpha cells which secrete glucagon is used instead)
-These cells incorporate the new DNA into their nucleus and are able to use protein synthesis to produced insulin
May affect function of Cytotoxic T cells to reduce autoimmune response

What are old synthetic hormoens from?

Derived from animals (predominantly pigs and cows)

What are the risk of synthetic hormones?

-Increased risk of contamination
-Animal had to be killed (religious beliefs)
-More expensive and less hormone produced
-May cause immune response

What are new synthetic hormones created from?

Recombinant DNA (bacterial cells)

What are the benefits of new syntehtic hormones?

-Reduced risk of contamination
-Cheaper to produced
-Can be made in larger quantities
-Won't pass on animal-borne diseases

What does using altered stem cell achieve?

Using altered stem cells instead of mature somatic cells (general cells) achieve longer lasting results in many patients