Season 3, Episode 3: Strangers in the Night

An outbreak in San Francisco of a virus causing symptoms similar to pneumonia and West Nile Virus starts killing 30-40 year olds. But none of the victims appear to have been bitten by mosquitoes nor do they know each other. It’s not clear how the disease is spreading but one patient has a milder version of the disease. He also happens to be taking a drug called interferon for an unrelated illness. The NorBAC team thinks he might be the clue to battling this mystery virus. Meanwhile, Owen wants to be the research subject in a scientist’s attempt to cure addiction…

Image provided courtesy of Shaftesbury Films.

David, Carlos and a local physician observe patients infected with the “Sinatra” virus.

IS IT POSSIBLE TO BOOST THE IMMUNE SYSTEM’S ABILITY TO FIGHT DISEASE WITH INTERFERON?

What is interferon and what is it used for?

Interferon is a group of related proteins made by cells of the body that have been infected by virus or bacteria. Some tumors also trigger interferon release. There are three types of interferons—called alpha, beta and gamma—that together activate the body’s immune defenses.

How does interferon boost the immune system?

Interferon activates so-called signaling pathways. In infected or cancerous cells, interferon can activate signals that prevent cells from dividing, which stops infection spread or tumor growth. Infected cells make and release interferon to signal to other immune cells like natural killer cells or macrophages, which can in turn kill infected cells to prevent further infection.

So…

Yes, interferon is prescribed as a medication to fight a number of diseases including certain leukemias, Kaposi's sarcoma, human papillomavirus and hepatitis B and C. Interferon-gamma is used to treat chronic granulomatous disease, which is an inherited disorder that prevents certain immune cells from fighting bacterial infections.

IS IT PROBABLE THAT ADDICTION CAN BE “REMOVED?”

Image provided courtesy of Shaftesbury Films.

Owen tells David about his intention to undergo an experimental treatment to cure his addictive behaviour.

How do genes affect behavior?

Behaviours like addiction are called complex traits. Although genetics might factor into one's predisposition to particular behaviours, social and environmental factors also can heavily influence the same behaviours.

To look for a genetic component of addiction, researchers look at the genetic material-the DNA-of people who have addictions and compare patterns with the DNA from people who do not. They then use math and statistics to determine whether genetic differences correlate with specific addictive behaviours.

The field of so-called behavioural genetics is an area of active research. One approach to learn more about the genetic underpinnings of behaviour is to study the genes in the dog genome. Different dog breeds share nearly 100 percent of their genetic sequence but display very different behavioural tendencies. Border collies herd while Newfoundlands swim. What do the puppies do if these two dogs are interbred? A little bit of both, it turns out, depending on the individual puppy. By looking at the slight differences in DNA sequences across breeds, scientists may uncover the genes that influence their different behaviours.

How does one “remove” a gene?

Image provided courtesy of AXS Studio Inc.

The DNA double helix.

Many types of organisms can be genetically engineered to lack a gene or to render a gene nonfunctional. Although this has not yet been done in humans, one promise of successful gene therapy is to target and turn on or off specific genes. For example, gene therapy would aim to turn off genes that cause cancer growth to curb the disease.

One way to turn off genes is by a technique called RNA interference, the discovery of which was recognized with the 2006 Nobel Prize in Medicine. Introducing small bits of RNA into cells "gums up" other RNAs that are on their way to being translated into proteins. The gummed up RNAs get chewed up and destroyed instead, which prevents the protein from ever being made and effectively turns off the gene that generated that RNA.

Nonetheless, the challenges facing gene therapy include targeting the correct cells and targeting the correct gene within those cells without introducing other and potentially dangerous changes in the DNA. Currently, researchers are studying ways in which viruses can be engineered to infect specific cells.

So…

As a complex trait that’s determined by both genetics and environment, addiction probably cannot be “removed” by gene therapy alone.

- by Audrey M. Huang, Ph.D.

Want to read and learn more?

To learn more about how the immune system works, visit:
http://health.howstuffworks.com/immune-system.htm

To learn more about the genetics of addiction, visit:
http://learn.genetics.utah.edu/units/addiction/genetics/

To learn more about the Dog Genome Project, visit:
http://research.nhgri.nih.gov/dog_genome/

To learn more about RNA interference, visit:
http://nobelprize.org/nobel_prizes/medicine/laureates/2006/illpres/index.html