Peanut allergies, which affect 3 million U.S. residents and kill approximately 150 U.S. residents every year, may soon be a thing of the past, thanks to biotechnology.
Writing in the May 3 issue of the British medical journal The Lancet, Duke University researcher Wesley Burks reports scientists are working on ways to genetically modify peanuts to strip them of their allergen properties.
Severe Allergies Rising
Anaphylaxis is a catastrophic, life-threatening allergic reaction that kills a few hundred people in America each year. One of the notorious causes of anaphylaxis is bee stings for people who are sensitive, so these sensitive people carry around with them epinephrine (adrenalin) to inject if they are stung.
Another well-known cause of anaphylaxis is foods, particularly nuts, both ground and tree nuts. The reaction to foods can be like that to a bee sting, swelling of the throat and breathing passages, asthma, skin welts, itching, flushing … or quick and deadly loss of circulation, called anaphylactic shock.
An increasing number of people, especially young and middle-aged persons, are developing severe peanut allergies. Because of this, some schools and airlines have outlawed peanuts, for fear a sensitive person might inhale peanut dust or otherwise accidentally come in contact with a peanut.
Tackling a Difficult Problem
Researchers at the University of Florida in 2006 announced their discovery of a less-allergenic peanut protein. The problem with genetically modifying peanuts, however, is that there are multiple allergy-causing proteins in them, and the changes may result in a lesser peanut.
“An example would be to introduce anti-sense RNA copies of the allergen gene into the peanut plant to suppress allergen gene expression,” reported Burks. “Post-translational gene silencing by mRNA degradation is another approach being investigated.
“The difficulty with this and similar approaches is that several peanut proteins are involved in IgE [immunoglobin E] binding,” Burks added.
That means finding a way to produce a better peanut will take a good deal of time and research, but scientists such as Burks believe an answer may arise soon.
Why More Allergic Reactions?
In addition to investigating the substances that cause allergies, scientists have been asking why more people have been developing allergies–and particularly severe ones–to peanuts and other environmental factors in recent years.
Two good theories currently under scientific consideration are (1) a lack of allergen stimulation in a cleaner and less allergen-loaded environment leads to greater sensitivity, as suggested in the September 19, 2002 New England Journal of Medicine and (2) a reduction in childhood infections is causing a more sensitive population, since children who have had type 1 infections in their first two years of life are less likely to have the type 2 response to later allergic challenges. That theory was explored in the British Medical Journal in April 2001.
While scientists continue to investigate genetic modifications that will reduce or eliminate incidents of anaphylaxis, peanuts for now remain a deadly threat to many people.
John Dale Dunn, M.D., J.D. ([email protected]) is a member of the civilian emergency medicine faculty at the Carl R. Darnall Army Medical Center, Fort Hood, Texas, and a policy advisor for the American Council on Science and Health.
For more information …
“Eat Dirt–The Hygiene Hypothesis and Allergic Diseases,” S. T. Weiss, New England Journal of Medicine, September 19, 2002: http://content.nejm.org/cgi/content/short/347/12/930
“The Protective Effect of Childhood Infections,” British Medical Journal, February 17, 2001: http://www.bmj.com/cgi/content/full/322/7283/376