Peanut Allergy Linked to Genes
A gene defect that can triple the risk of a child developing an allergy to peanuts has been identified, an international research team led by scientists from Dundee University in the United Kingdom reported recently. The gene, which is called Filaggrin, has already been shown to be a factor in causing eczema and asthma.
The number of people affected by peanut allergy has increased dramatically over the past 20 to 30 years, the Dundee-based team reported, but the causes of the allergy are unknown. Dr. Sara Brown, a fellow at Dundee University, said investigating whether Filaggrin was a cause of peanut allergy was the "logical next step" after a link with eczema and asthma had been established. Brown says that since allergic conditions run in families, "inherited genetic factors are important."
The results of the study show that one in five of all peanut allergy sufferers have a Filaggrin defect. Those with the defect can be three times more likely to suffer peanut allergy than people with normal Filaggrin.
Professor Irwin McLean, also based at Dundee University and a leading expert on the gene Filaggrin, said the Filaggrin defect was not the only cause of peanut allergy but that it had been established as a factor in many cases. The study authors also noted that environmental changes and increased exposure to peanuts can contribute to the increase in peanut allergy in Western Europe and the U.S.
This study marks "the first time that we have a genetic change that can be firmly linked to peanut allergy," Brown says.
Brown and other researchers from the United Kingdom, Canada, Ireland and the Netherlands published their findings online in the Journal of Allergy and Clinical Immunology this spring. For more information, visit www.jcaionline.org.