Science ( IF 41.845 ) Pub Date : 2020-11-20 , DOI: 10.1126/science.abe8283 Marc E. Rothenberg
Allergic diseases, which affect 10 to 30% of the global population, have a high degree of heritability contributed by a combination of parental factors (1). In addition to genetics, such parental factors include the amount of maternal immunoglobulin E (IgE), the antibody type that binds to allergens, which directly correlates with the risk of allergy in offspring (2). On page 941 of this issue, Msallam et al. (3) delve into the relationship of maternal IgE and fetal mast cells in mice and humans, demonstrating that IgE crosses the placenta and binds to fetal mast cells, and relate this to the subsequent development of allergic responses in offspring.