Antisense RNA technology is a treatment for genetic disorders or infections that involves turning off the gene causing the disease. This is done by synthesizing a strand of DNA or RNA that binds to the mRNA produced by the gene and deactivates it. Antisense RNA technology has been largely unsuccessful due to its toxicity, problems with delivery methods, instability, manufacturing cost, administration and circulation time.
Antisense RNA is so named because its sequence of nucleotides is the complement to that of the mRNA, called "sense." The mRNA is a single-stranded string of nucleotides that results from the production of proteins based on the gene. Normally, in order to produce a protein, the mRNA is read by transfer RNAs, but antisense RNA strands block the translation. The transcription is also blocked because the duplex RNA is quickly degraded in the cell. Antisense molecules are more toxic than other drugs because they also affect other genes, a result of the stimulation of the immune system. Additionally, the delivery of antisense molecules into the necessary organs is not fully understood and the molecules do not remain stable in human cells for long. Antisense RNA is time-consuming to manufacture, can only be administered intravenously and is typically cleared from the body within an hour.