A team of US-based researchers has discovered a region in the human genome that seems to be associated with peanut allergy - the most common food allergy among children, which can be fatal. Writing in the journal Nature Communications, the team analysed DNA from more than 2,500 children and parents enrolled in a large food allergy study. Scanning around a million genetic markers across the human genome, the team found that variations in a region of the genome harbouring certain genes known as HLA genes, short for human leukocyte antigen, were linked to the risk of developing food allergies, including peanut allergy.
In total, the variations they found accounted for about 20 percent of peanut allergy in the people in the study, but not everyone with the variations had the allergy. The researchers think that other changes in the genome known as epigenetic changes - chemical tags added on to DNA which don't affect the underlying DNA code itself - might explain these differences in susceptibility. Intriguingly, these epigenetic marks can be altered by the environment, including the diet, but more research is needed to figure out how all these variations and changes fit together to increase allergy risk.
Food allergies are rising rapidly in the US and Europe, and scientists are searching for answers as to why this might be the case. By understanding the interplay between inherited genetic variations and the environment, it might be possible to predict the risk of severe food allergies in future, and even develop drugs or diet or lifestyle interventions that help to control or even prevent them.