Allergies - from arthropods to hay fever

Allergies manifest in many different ways and due to many different allergens. Some allergic reactions are mild; others are life-threatening, but all can be described as being irritating - to put it mildly - abnormal immune responses to everyday things.

Allergies are common diseases and seem to become all the more prevalent [1, 2]. Genetic makeup in your DNA is undoubtedly a role player in developing allergic diseases, where environmental factors are major mediators [2].

An allergic reaction is a hypersensitive reaction of the immune system with harmful rather than protective effects [1]. Allergic reactions frequently involve the over-production of immunoglobulin (IgE) antibodies in response to an allergen [2]. This kind of reaction is heritable.

Atopy, or the genetic tendency to develop allergic diseases, can include food allergies, eczema, asthma, and hay fever. Common non-food allergens include pollen, house dust mites, and cat dander [1, 2]. Allergies rarely occur in isolation, i.e., one is commonly allergic to more than one food.

Similarly, eczema, asthma, and hay fever are frequent partners with one another as well as food allergies. This “partnering” of allergies is due to overlapping role-playing genes [3, 4]. Not all allergic reactions and allergic diseases are related to IgE antibodies. Non-IgE allergies include skin rashes that occur due to contact with substances that irritate the skin. Asthma and food allergies may also be non-atopic [2, 5].

The genetic predisposition towards allergic diseases is dependent on many genes and the interaction with the environment [6]. Genetic predisposition to allergies can thus not be precisely predicted. However, identifying specific gene variants can inform you of your risk to contract an allergy. Gene variants that are associated with a likelihood of suffering from allergic diseases have been identified. These allergic diseases include having hay fever, being allergic to eggs, peanuts, and even cockroaches.

Well, I have an allergic predisposition, what now? This depends on the type of allergy. But understanding your condition is the first step towards gaining control. To proactively act to the genetic predisposition of allergies, one can prevent the development of allergic diseases for both yourself and your children.

Exposure to microbes seems crucial for the proper development of the immune system and response to common allergens. Thus, living in too clean environment can thus have adverse effects regarding the proper development of the immune system [1]. Being overly protected against exposure to potential allergens early in life could increase the risk of becoming allergic to them.

These are common reasons for the onset of allergies related to food, eczema, asthma, and hay fever [2, 7]. The same substances that can cause allergic reactions may also protect against the development of allergies. It has been found that a significant determining factor may be at what age you are first exposed to the substance. Exposure to a potential allergen within the first year of life may have protective effects [2].

Food allergies are most prevalent in children [8]. Egg allergy and peanut allergy are amongst the most common food allergies [5]. Children usually develop an egg allergy within their first year. However, most outgrow it, usually from three to six years [8]. Introduction of all solid foods is recommended from the age of 6 months. Waiting longer than this increases the risk for all common food allergies [8, 9].

Interestingly, egg yolks are not usually the problem associated with an allergy to eggs; it is egg whites that elicit an IgE response. Allergy testing involves eating eggs under medical supervision. Otherwise, a history of allergy symptoms after eating egg or egg products, together with a skin test, or testing for egg-specific IgE, is used for diagnosis [8].

An allergy to peanuts can be serious and is more likely to involve anaphylaxis [10]. Even minimal amounts of peanuts may cause severe reactions. The protein in peanuts are the allergens which there are 16 of [11]. This allergy is also more likely to remain long-term [10].

A third major factor that plays a role in the development of allergies is the gut microbiome. The gut microbiome is comprised of all the bacteria and microorganisms that are present in your intestines. The composition and diversity of gut bacteria in infants have been linked with the development of various body function systems. The metabolic, mental, and immune systems are all impacted by the gut’s health. The gut’s health is determined by its bacteria content [7].

The development of the immune system is linked to the risk of developing allergies. The development of normal immune responses is greatly influenced by gut bacteria and proper nutrition from very early in life [7].

One wants to have diverse and healthy colonization of gut bacteria. Being birthed naturally, steering clear of antibiotics, and ensuring good nutrition from infancy all contribute towards a healthy gut. Breastfeeding is also said to be protective against the development of allergies. Breast milk contains needed allergens and immune boosters that are not in artificial formulas [7].

Although precise protocols still need to be established, treatment options are available for food allergies. Treatments aim to build up immune tolerance for the foods that cause reactions. Most forms of therapy involve gradual exposure to the foods people are allergic to. The idea is to cause desensitization [5]. Treatment of allergies should be undertaken only under the supervision or guidance of your doctor. It is also recommended to consult with a dietitian if you have a food allergy. They will be able to guide you through a healthy diet plan.

BioCertica can test for your genetic predisposition to develop an egg, peanut, or cockroach allergy. Testing your genes can also shine a light on whether your common cold symptoms are actually seasonal hay fever.

References:

[1] Kay, A. B. (2001). Allergy and Allergic Diseases. The New England Journal of Medicine, 344(1), 30–37.

[2] Murrison, L. B., Brandt, E. B., Myers, J. B., & Khurana Hershey, G. K. (2019). Environmental exposures and mechanisms in allergy and asthma development. Journal of Clinical Investigation, 129(4), 1504–1515. https://doi.org/10.1172/JCI124612

[3] du Toit, G., Sayre, P. H., Roberts, G., Lawson, K., Sever, M. L., Bahnson, H. T., Fisher, H. R., Feeney, M., Radulovic, S., Basting, M., Plaut, M., Lack, G., Chan, S., Fox, A., Abraham, M., Adam, M., Coverdale, L., Duncan, C., Nixon, A., … Mason, T. (2018). Allergen specificity of early peanut consumption and effect on development of allergic disease in the Learning Early About Peanut Allergy study cohort. Journal of Allergy and Clinical Immunology, 141(4), 1343–1353. https://doi.org/10.1016/j.jaci.2017.09.034

[4] Johansson, Å., Rask-Andersen, M., Karlsson, T., & Ek, W. E. (2019). Genome-wide association analysis of 350 000 Caucasians from the UK Biobank identifies novel loci for asthma, hay fever and eczema. Human Molecular Genetics, 28(23), 4022–4041. https://doi.org/10.1093/hmg/ddz175

[5] Licari, A., Manti, S., Marseglia, A., Brambilla, I., Votto, M., Castagnoli, R., Leonardi, S., & Marseglia, G. L. (2019). Food allergies: Current and future treatments. Medicina (Lithuania), 55(5), 1–13. https://doi.org/10.3390/medicina55050120

[6] Fiuza, B. S. D., Fonseca, H. F., Meirelles, P. M., Marques, C. R., da Silva, T. M., & Figueiredo, C. A. (2021). Understanding Asthma and Allergies by the Lens of Biodiversity and Epigenetic Changes. Frontiers in Immunology, 12(March), 1–18. https://doi.org/10.3389/fimmu.2021.623737

[7] Wopereis, H., Sim, K., Shaw, A., Warner, J. O., Knol, J., & Kroll, J. S. (2018). Intestinal microbiota in infants at high risk for allergy: Effects of prebiotics and role in eczema development. Journal of Allergy and Clinical Immunology, 141(4), 1334-1342.e5. https://doi.org/10.1016/j.jaci.2017.05.054

[8] Anagnostou, A. (2021). Optimizing patient care in egg allergy diagnosis and treatment. Journal of Asthma and Allergy, 14, 621–628. https://doi.org/10.2147/JAA.S283307

[9] Hicke-Roberts, A., Wennergren, G., & Hesselmar, B. (2020). Late introduction of solids into infants’ diets may increase the risk of food allergy development. BMC Pediatrics, 20(1), 1–9. https://doi.org/10.1186/s12887-020-02158-x

[10] Al-Ahmed, N., Alsowaidi, S., & Vadas, P. (2008). Peanut allergy: An overview. Allergy, Asthma and Clinical Immunology, 4(4), 139–143. https://doi.org/10.2310/7480.2008.00021

[11] Shah, F., Shi, A., Ashley, J., Kronfel, C., Wang, Q., Maleki, S. J., Adhikari, B., & Zhang, J. (2019). Peanut Allergy: Characteristics and Approaches for Mitigation. Comprehensive Reviews in Food Science and Food Safety, 18(5), 1361–1387. https://doi.org/10.1111/1541-4337.12472