Advances in Asthma and Allergic Disease Genetics – Is Bigger Always Better?

Abstract This review focuses on genome-wide association studies (GWASs) of asthma and allergic diseases published between January 1, 2018 and June 30, 2019. During this time period there were 38 GWASs reported in 19 papers, including the largest performed to date for many of these conditions. Overall, we learned that childhood onset asthma is associated with the most independent loci compared to other defined groups of asthma and allergic disease cases; adult onset asthma and moderate-to-severe asthma are associated with fewer genes, which are largely a subset of those associated with childhood onset asthma. There is significant genetic overlap between asthma and allergic diseases, particularly with respect to childhood onset asthma, which harbors genes that reflect the importance of barrier function biology, and to HLA region genes, which are the most frequently associated genes overall in both groups of diseases. Although the largest GWASs in African American and Latino/Hispanic populations were reported during this period, they are still significantly underpowered compared to studies reported in European ancestry populations, highlighting the need for larger studies, particularly in childhood onset asthma and allergic diseases, in these important populations that carry the greatest burden of disease.