Genetic and Environmental Causes

Asthma is a complex disease with genetic and environmental causes. It affects more than 6% of children in the developed world (Fanta, 2009). Because of its complexity, candidate genes for asthma have been difficult to determine. In 2010, our group published a genome-wide association study (GWAS) of 3,377 children with asthma and 5,579 healthy children. GWAS allows us to examine genetic variations across an individual’s entire genome, and compare variations between affected and unaffected groups. We discovered a region on chromosome 17 and a previously unassociated region on chromosome 1 that strongly correlated with susceptibility to asthma. The region in chromosome 1 was especially associated with asthma in the children of African ancestry, and contains a gene, DENND1B, that is expressed by natural killer cells – a critical component of the immune system. Targeting the DENND1B gene may be a promising avenue for future treatments of asthma.

Patrick Sleiman was first author on this paper, which was published in the New England Journal of Medicine.