Eosinophilic Esophagitis (EoE) is a chronic allergic condition of the esophagus, the tube connecting the mouth and stomach. In people with EoE, white blood cells called eosinophils gather in the esophageal lining and cause inflammation. This response can lead to symptoms such as difficulty swallowing, chest pain, and food getting stuck in both children and adults.
The Role of Genetics in EoE
Eosinophilic Esophagitis has a hereditary component, as the condition often appears in multiple family members. Studies show that relatives of individuals with EoE are more likely to develop the disease than the general population. This clustering of cases within families points toward a shared genetic susceptibility.
EoE is a polygenic condition, meaning its development is influenced by multiple genes rather than a single one, which explains its complex inheritance pattern. Researchers have identified specific genes that increase risk for EoE. These genes often regulate immune responses or maintain the integrity of the esophageal barrier.
Two well-studied genes linked to EoE are TSLP and CAPN14. The TSLP gene is involved in signaling pathways that trigger allergic inflammation, and variations can make the immune system overreactive. The CAPN14 gene is expressed in the esophageal lining and affects the strength of its protective barrier.
Environmental Triggers and Influences
A genetic predisposition alone is not enough to cause EoE; the disease requires an environmental trigger to become active. This gene-environment interaction explains why some genetically susceptible individuals develop symptoms while others do not. External factors act as the switch that initiates the inflammation.
The most common triggers are food allergens, causing a delayed allergic response to proteins in foods like dairy, wheat, eggs, and soy. Identifying and removing these trigger foods from the diet is a primary management strategy.
Inhaled allergens like pollen, dust mites, and mold spores can also contribute to EoE when swallowed. This exposure can initiate or worsen the inflammatory process. The influence of airborne allergens helps explain why some people experience seasonal fluctuations in their symptoms.
Assessing Risk Within Families
The risk for EoE is significantly higher within affected families. First-degree relatives, such as parents, siblings, and children, of a person with EoE have a 10 to 40 times greater chance of developing the condition than the general population.
This heightened risk is connected to a broader predisposition to atopic, or allergic, conditions. It is common for individuals with EoE, or their close relatives, to also have a history of asthma, eczema, or seasonal allergies. This pattern is sometimes referred to as the “atopic march.”
The presence of these other atopic diseases within a family indicates a shared genetic tendency toward allergic responses. When assessing risk, clinicians consider a family history of EoE and the prevalence of related allergic disorders.
Implications for Diagnosis and Management
Individuals with symptoms like trouble swallowing or food impaction should inform their healthcare provider about any family history of the disease. This knowledge can prompt a physician to consider EoE earlier in the diagnostic process, potentially leading to a more timely diagnosis.
A family history of EoE or other atopic diseases may influence the decision to perform an upper endoscopy and biopsy, the only definitive diagnostic test. Early diagnosis allows for management strategies that control inflammation and prevent long-term complications like esophageal scarring.
Genetic testing for specific EoE-related genes is not a standard part of clinical diagnosis. Because the disease is polygenic, a single genetic test cannot predict who will develop the condition. The focus remains on clinical symptoms and endoscopic findings, with family history serving as a contextual factor.