SNPwatch: Genetic Variant Associated with Food Allergy-related Disorder Eosinophilic Esophagitis

For the millions of children and adults with severe food allergies, ingesting even tiny quantities of some of the most basic foods can result in a potentially deadly reaction.   Milk, eggs, nuts, fish, shellfish, soy and wheat are some of the most common offenders.Some people with food sensitivities have something more than just a food allergy.   Eosinophilic esophagitis (EoE) is a condition in which exposure to certain foods causes the inappropriate migration of immune cells called eosinophils to the lining of the esophagus, where they release factors that lead to inflammation and swelling.   This can result in feeding difficulties and failure to thrive in young children, and difficulty in swallowing in adults.   Other symptoms include heartburn, vomiting and food impaction in the esophagus.   About one in 10,000 people is thought to have EoE, although some researchers think this may be an underestimate.Studies indicate that EoE has a strong genetic component, but previous research has linked only one gene to the condition.   However, in a recent issue of the journal Nature Genetics, researchers from Cincinnati Children’s Hospital Medical Center and the Children’s Hospital of Philadelphia presented results of a genome-wide associations study of EoE that indicate that a gene known to play a role in asthma and atopic dermatitis (a type of eczema) is also associated with the condition.A total of 351 people with EoE and 3,140 unaffected controls, all children and young adults of European ancestry, were studied to find genetic variations associated with the condition.   The strongest association with EoE revealed by the DNA analysis was with a SNP near the TSLP gene.   The slightly less common G version of this SNP was found more often in controls than cases of EoE, suggesting that it confers protection against the condition.   Each copy of the G version was associated with 0.53 times odds of EoE compared to having two copies of the A version in the first group studied, and 0.73 times odds in a replication group.The researchers looked at esophagus tissue samples to learn more about TSLP.   They found that the gene is turned on at higher levels in people with EoE, and that there is a correlation between having the protective G version of and lower levels of the TSLP protein.The TSLP protein is known to regulate inflammatory responses.   It is a key initiator of allergic inflammatory diseases and has been shown to be overproduced in atopic dermatitis lesions and asthma-affected lungs.   People with EoE often also suffer from these other allergic conditions.“Eosinophilic esophagitis is a highly allergic disease, and one that is rapidly expanding,” said Jonathan M. Spergel, director of the Center for Pediatric Eosinophilic Disorders at the Children’s Hospital of Philadelphia and a co-first author of the study, in a press release.“This is the first genome-wide association study done of this disease, and now that we have elucidated a gene pathway, the hope is that physicians can eventually intervene in that pathway and discover a new treatment.”SNPwatch gives you the latest news about research linking various traits and conditions to individual genetic variations. These studies are exciting because they offer a glimpse into how genetics may affect our bodies and health; but in most cases, more work is needed before this research can provide information of value to individuals. For that reason it is important to remember that like all information we provide, the studies we describe in SNPwatch are for research and educational purposes only. SNPwatch is not intended to be a substitute for professional medical advice; you should always seek the advice of your physician or other appropriate healthcare professional with any questions you may have regarding diagnosis, cure, treatment or prevention of any disease or other medical condition.
  • I have GG on that rs and to be honest, I am quite relieved to find this info. I have suffered many different allergies since childhood. Today most annoying are the skin problems. Atopic skin.

  • Victoria

    I hope more and more research is done on this. My Father, myself and my children have severe food allergies. In my young twins it was causing severe vomiting with the girl and autism type symptoms with the boy. After we removed the foods both children are doing fine without medications.

  • Daizy

    Very interested to learn about Eosinophilic Esophagitis. I was very allergic to wool and cats, as a child, but had no food allergies. As an adult, I periodically suffer from food impactions and difficulty swallowing. With my first episode of this serious dysphagia I learned that I could still breathe and with relaxation and enough time, sometime being hours, it would resolve.

    Over the years I have a better feeling for when an esophagitis impaction is starting and can stop eating. I still have perhaps half a dozen or more episodes every year. I think for me, stress plays a role in the onset of an esophagitis impaction. Do others find stress is a trigger? Is that a different problem?

  • JimmyG

    I have suffered from something like this too, and have the same symptoms and response that Daizy describes… I can tell when it’s coming now and as long as I stop eating (and talking, which is hard at a family dinner table) I can usually avoid the situation. I also have started to develop a way of swallowing ‘over’ the impaction that seems to help. It got bad enough 10 years ago that I actually had the lower esophogus dilated, and the impaction may actually be formed by a ‘web’ that either formed or was hereditary. This solved my issue for years, and it is now starting to come back. I find there are certain foods that seem to cause this more than others..

    BTW I am AA for this SNP.