What are the diseases can be treated by gene and cell therapy currently?

Gene therapy involves altering the genes inside your body's cells in an effort to treat or stop the disease.

Genes contain your DNA, the code that controls much of the form and function of your body, from growing you to regulating your body's systems. Genes that don't work properly can cause disease.

Gene therapy replaces a faulty gene or adds a new gene in an attempt to cure a disease or improve your body's ability to fight it. Gene therapy holds promise for the treatment of a wide range of diseases, including cancer, cystic fibrosis, heart disease, diabetes, hemophilia and AIDS.

Gene therapy is used to correct defective genes in order to cure a disease or help your body fight disease better.

Researchers are investigating several ways to do this, including

• Replacing mutated genes. Some cells become sick because certain genes work incorrectly or no longer work at all. Replacing defective genes may help treat certain diseases. For example, a gene called p53 normally prevents tumour growth. Several types of cancer have been linked to problems with the p53 gene. If doctors can replace the defective p53 gene, it could cause the cancer cells to die.Some cells become sick because certain genes work incorrectly or no longer work at all. Replacing defective genes may help treat certain diseases. For example, a gene called p53 normally prevents tumour growth. Several types of cancer have been linked to problems with the p53 gene. If doctors can replace the defective p53 gene, it could cause the cancer cells to die.
• Fixing mutated genes. Mutated genes that cause disease can be turned off so they no longer promote disease, or healthy genes that help prevent disease can be turned on so they can inhibit disease.
  
• Make sick cells more evident to the immune system. In some cases, your immune system does not attack the sick cells because it does not recognise them as intruders. Doctors may use gene therapy to train your immune system to recognise cells that are a threat.