GENE THERAPY

Gene therapy

 Gene therapy is the medical approach to correcting a gene to cure a disease or disorder. There are a number of diseases that are caused by dysfunctional genes or due to the gain of function of a gene.  Genes express themselves by synthesizing proteins. If a protein is required for a metabolic process and this protein is non-functional due to defected gene, the metabolism is affected. Curing the protein is a process of re-establishing the metabolism. This can be done by curing the gene or transferring the correct gene into the organism.

 Gene therapy includes somatic gene therapy where, genes are edited or transferred into somatic cells of the organism. This therapy cures the disease in an individual. But it is not inheritable as the gene is edited in somatic cells. This can be used for genes that are specific in their expression in the organism.  Somatic gene therapy includes gene transfer and gene editing.

SOMATIC CELL GENE THERAPY

Gene editing involves the specific technique of knocking out or knocking in the new gene. This uses crisper cas 9 Technology.

  The transfer of genes is used for somatic gene therapy. However, vectors can be used to deliver genes to a specific site. Even though intravenous gene transfer can be done. For this virus vectors are used. These viruses will deliver the correct gene to the site of its requirement.

The embryonic gene is the gene therapy where embryonic stem cells are cured for defected genes.

  Gene editing may be used in embryonic gene therapy. Here, the organism is cured in the embryonic stage only. Gene transfer can also be used in the embryonic cell stage.

RNA EDITING

 The new organism that is born will have corrected gene function. However, this approach has broad applicability but it is not allowed on the ethical ground. The embryonic stem cell gene therapy may lead to human cloning and the formation of designer babies.

 Uses of gene therapy

 It utilizes the organism-specific approach to cure a disease. No chemical drugs or antibiotics are used in therapy to avoid their side effects.

 Gene therapy genetic disorders can be corrected for which rarely any curing approach is available. Cancer can be cured through gene therapy without utilizing chemotherapy or radiotherapy that is destructive to human health. Spinal muscular dystrophy can be cured through gene therapy.

 Immunosuppressant diseases are also cured by gene therapy.

 Leukemia can be cured through gene therapy.

 Crisper cas9 Technology

 Crisper cas 9 has a small guide RNA along with A nucleases. The guide RNA has a specific sequence. This is called PAM. This sequence binds to the targeted gene in nucleus and then recognizes the site for cutting the DNA. It cuts the DNA to either generate knock-out, where a gene is rendered dysfunctional or knock-in, where the gene is rendered functional. Crisper cas 9 Technology initiates the cellular mechanism of gene recombination. It can be done through homologous gene recombination or non-homologous gene recombination. Both of these mechanisms are well established in the cell, and they can generate knock-out or knock-in.