You may be born with your genes, but that doesn't mean you can't change them. Fixing genetic malfunctions by repairing "flaws" in the DNA code—using a technique called gene therapy—is no longer science fiction.

Essentially, gene therapy attacks the very root of a disease: the gene or genes causing the problem. The repair work involves adding corrective DNA to certain cells. And as scientists learn more and more about the locations and functions of genes, they can potentially fix an increasing number of disorders.

Gene Therapy: How It Works

Gene therapy is a young science, and right now it can't cure all genetic diseases—in fact, clinical trials can be risky. But some recent efforts have shown promise.

Viruses replace our cells' genetic material with their own. Now scientists can remove the DNA from a virus, substitute corrective DNA, and dispatch these tiny invaders into a patient's cells, where they do their work to our advantage.

Some people are concerned, however, that medical advances are outpacing ethical decisions. If we alter the genes of eggs and sperm, we can potentially remove genetic traits from entire populations. And as we develop gene therapies for life-threatening disorders, some say enhancements like changing height and hair color are likely to follow.

Gene Therapy

See a video of how gene therapy works.