Gene Therapy for Severe Combined Immune Deficiency Syndrome (SCID)

The very first successful gene therapy was used to treat SCID back in 1990. Often referred to as "bubble-boy syndrome," SCID is caused by a single defective gene, and causes the human immune system to fail. In other words, the body has no defenses against diseases like chicken pox or even the common cold.

Researchers believed that replacing the defective gene could reverse the effects. The first patient to undergo this experimental treatment was a 4-year-old girl suffering from SCID. The team of researchers injected copies of a working gene into specially engineered (created) viruses. The viruses were injected into the patient, "delivering" billions of the new healthy genes. The treatment was a success, but the patient must still receives drug therapy to help her stay healthy.