Gene therapy

Prepared by:Samira Fattah Hamid MSc in medical microbiology-college of medicine-HMU

outlines

1. What’s gene ?2. genetic disorders.3. Gene therapy.4. Gene delivery approaches.5. Concept of Gene Therapy.6. diseases treated with gene therapy.7. problems of gene therapy.

What’s gene ?• basic unit of heredity.• carried on a chromosome. • are segment of deoxyribonucleic acid (DNA) .

What’s gene ?• A gene consists of a long combination of four

different nucleotide bases: A (adenine)

C (cytosine) G (guanine)

T (thymine)

• Each person has thousands of genes and billions of base pairs of DNA which determine individual characteristics. and pass genetic traits to offspring.

• When genes are altered so that the encoded proteins are unable to carry out their normal functions, genetic disorders can result.

• Genetic disorders rarely have effective

treatments, though gene therapy is being tested as a possible treatment for some genetic diseases.

genetic disorders

Gene therapy

Is the insertion, alteration, or removal of genes within an individual's cells to treat diseases and hereditary diseases in which a defective mutant gene is replaced with a functional one.

• Replacing a mutated gene that causes disease with a healthy copy of the gene.

• Inactivating mutated gene that is functioning improperly.

Approaches for correcting faulty genes:

Gene delivery approaches

1-Physical methods

2-Viral vectors

Physical methods

Injection of naked DNA by:

electroporation.

Gene gun

Viral vectors Retroviruses Adenoviruses Herpes simplex viruses

Concept of Gene Therapy

Gene therapy utilizes two theoritically possible approaches :

2. Somatic gene therapy

1. Germline gene therapy

Germline gene therapy

• Involve the genetic modification of germ cells of an individual and would be carried on to future generations.

• This would offer the possibility of removing an inherited disorder from a family line forever.

Somatic Gene Therapy Transfer of a gene into body cells other than

germ cells with effect only on the patient. The new genetic material cannot be passed on to offspring

Somatic gene therapy can be broadly split into two categories :

1. Ex vivo

2. In vivo

What diseases could be treated withgene therapy

• About 4000 diseases have been traced to gene disorders.

• Current and possible candidates for gene therapy include: cancer AIDS Parkinson's disease Alzheimer’s disease cardiovascular diseases and arthritis

• Short-lived nature of gene therapy• Immune response• Problems with viral vectors• Multigene disorders 

 Problems of gene therapy

Summary

• Gene is the basic unit of heredity.• genetic disorders needs treatment by gene

therapy.• The aim is by replacing or inactivating a mutated

gene.• Gene therapy try to treate different types of

diseases.• During application gene therapy faced some

problems.