Gene Silencing

Another aspect of gene therapy is gene silencing, also called antisense technology. With this method, geneticists can inactivate a gene that may cause disease or be defective.

When DNA replicates, RNA bonds to half of the split double helix, making a mold of sorts. The RNA (messenger RNA or mRNA) is then used to create an identical DNA strand. To silence a gene on a chromosome, scientists, therefore, simply make an RNA strand 15-20 bases in length complementary to the mRNA. The synthesized RNA will attach itself to the mRNA and prevent that portion of the mRNA from creating the gene on the duplicate DNA strand. This method is highly specific.

Gene silencing is used to treat several viruses including AIDS, Herpes, Chicken Pox, and Hepatitis. More importantly, though, antisense technology is used by geneticists in research to learn what happens when certain genes are silenced.