What is gene therapy?

What is gene therapy?

Gene therapy is a medical treatment which alters the genetic structures of an individual’s cells. The method consists of replacing, modifying or insertion of genes into cells and tissues with the purpose of treating a disease (in most cases hereditary disease).

Types of gene therapy

• Germ line gene therapy

This therapy focuses on the future offspring of the patient because target cells for genetic modification are germ cells (sperm and eggs). Such genetic alteration is heritable and will manifest in future generations. Germ line therapy in humans is subject to ethical debates and prohibited by many jurisdictions although it is supposed to be very effective in preventing genetic disorders.

• Somatic gene therapy

In this case therapy will involve somatic cells of a patient and any modifications on the genome will affect the individual patient only, and will not be transmitted to the patient's offspring.

Gene therapy methods

• Insertion of a normal gene into the genome to replace a damaged nonfunctional gene
• Swapping of an abnormal gene with a normal one through homologous recombination
• Repairing a defective gene thorough selective reverse mutation
• Alteration of gene regulation (how is gene expressed)

Vectors in gene therapy

• viruses
• naked DNA
• oligonucleotides
• dendrimers