Gene therapy methodologies, clinical trial success and failures: Gene therapy clinical trials

A gene is the unit of heredity and carries inherited information

Amazing Facts of Human Genome

3 billion (3,000,000,000) letters in the DNA code in every cell in your body.

There is 6 feet of DNA in each of our cells packed into a structure only 0.0004

inches across (it would easily fit on the head of a pin).

There are 100 trillion (100,000,000,000,000) cells in the body

If all the DNA in the human body was put end to end it would reach to the sun

and back over 600 times (100 trillion x 6 feet divided by 93 million miles = 1200).

If we recited the genome at one letter per second for 24 hours a day

it would take a century to recite the book of life.

The vast majority of DNA in the human genome - 97% - has no known function.

Our DNA is 98% identical to that of chimpanzees.

Between humans, our DNA differs by only 0.2%, or 1 in 500 bases (letters).

(This takes into account that human cells have two copies of the genome.)

The estimated number of genes in both humans and mice is 30,000-45,000

in the round worm (C. elegans), the number is approximately 19,000.

Three examples of protein functions

–Catalysis: Almost all chemical reactions in a living cell are catalyzed by protein enzymes.

–Transport proteins transports various substances, such as oxygen, ions, and so on.

–Information transfer For example, hormones. –Are carried on a chromosome––The basic unit of heredity

––Encode how to make a protein––Proteins carry out most of life’s function.–When altered causes dysfunction of a protein When there is a mutation in the gene, then it will change the codon, which will change which amino acid is called for which will change the conformation of the protein which will change the function of the protein. Genetic disorders result from mutations in the genome. Imagine that you accidentally broke one of your neighbor's windowsStay silent: no one will ever find out that you are guilty, but the window doesn't get fixed Repair it with some tape: not the best long-term solution .Put in a new window: not only do you solve the problem, but also you do the honorable thing Gene therapy using an Adenovirus vector.A new gene is inserted into an adenovirus vector, which is used to introduce the modified DNA into a human cell. If the treatment is successful, the new gene will make a functional protein.

1. –1-one single gene–Cystic fibrosis–Severe combined immunodeficiency–Adenosine deaminase and purine nucleoside phosphorylase 
2. –2- gene therapy for cancer–3-gene therapy for cardiovascular diseases lType
   • 1: Single locus (gene) is defective and responsible for
     l the disease, 100% heritable.l : Sickle cell anemia,l Hypercholesterolemial Cystic fibrosis llType
   • 2: Polygenic traits, <100% heritable, may be dependentl on environmental factors and lifestyle.l Heart diseasel Cancerl Diabetesl Alcoholisml Schizophrenial Criminal behavior .-An abnormal gene traded for a normal gene

- An abnormal gene repaired through selective reverse mutation.-Change the regulation of gene pairs

Gene Therapy mainly aim to lSupplement a defective mutant alleleWith a functional one ideal vector characteristics:

.nsert size: one or more genes.

Targeted: limited to a cell type.

No immune response..4Stable: not mutated..5Production: easy to produce high concentrations (titer).. Regulatable: produce enough protein to cause an effect.