Allergies to food and airborne allergens in children and adolescents : role of epigenetics in a changing environment

Abstract

Allergic diseases today affect millions of children and adolescents worldwide. In this review, we focus on allergies to food and airborne allergens, and provide examples of prevalence trends during a time when climate change is of increasing concern. Profound environmental changes have affected natural systems in terms of biodiversity loss, air pollution levels and climate change. We discuss potential links between these changes and allergic diseases in children, as well as clinical implications. Several exposures of relevance for allergic disease also correlate with epigenetic changes such as DNA-methylation levels. We propose that epigenetics may offer a promising tool by which exposures and hazards related to a changing environment may be captured. Epigenetics may also provide promising biomarkers and help elucidation of mechanisms related to allergic disease initiation and progress.

Key messages:

• Allergic diseases affect millions of children and adolescents worldwide; between 5 and 30% of adolescents report rhino-conjunctivitis symptoms and up to 10 % report food allergy.

• Links between climate change and allergic diseases are of increasing concern, and these include: extended and altered pollen seasons, spread of allergens to new areas along with changing and warmer climate, air pollution exposures changes, increasing exposure to heat events, and altered biodiversity.

• These new climate change aspects of allergic diseases have clinical implications for prevention, diagnostics and treatment.

• Epigenetic changes, exemplified by DNA methylation, are associated both with environmental exposures and allergic diseases, although causality needs to be explored further.

• There is potential in the use of epigenetic signatures and omics profiles to detect and monitor aspects of environmental exposures of relevance for health and disease in children and adolescents.