A new study which involved the collaberative research efforts from centers in five countries was published in the journal of Nature Genetics. The research team identified a mutated gene associated with a high risk of severe childhood asthma by conducting a genome-wide association study (GWAS) on DNA from Danish national health registries and the Danish National Screening Biobank. The genomes from 1,173 children aged 2 to 6 years from the Copenhagen Prospective Study on Asthma in Childhood (COSPAC) was compared with genomes from 2,522 adult and pediatric control subjects without asthma.
The researchers identified a novel gene called CDHR3, (which is particularly active in epithelial cells lining the surfaces of airways), in addition to confirming the four genes previously implicated as asthma susceptibility genes.
“Because asthma is a complex disease, with multiple interacting causes, we concentrated on a specific phenotype — severe, recurrent asthma occurring between ages two and six,” said co-lead author of the study, Hakon Hakonarson, M.D., Ph.D., director of the Center for Applied Genomics at The Children’s Hospital of Philadelphia (CHOP). “Identifying a risk susceptibility gene linked to this phenotype may lead to more effective, targeted treatments for this type of childhood asthma.”
“Asthma researchers have been increasingly interested in the role of the airway epithelium in the development of asthma,” said Hakonarson, a pediatric pulmonologist. “Abnormalities in the epithelial cells may increase a patient’s risk to environmental triggers by exaggerating immune responses and making the airway overreact. Because the CDHR3 gene is related to a family of proteins involved in cell adhesion and cell-to-cell interaction, it is plausible that variations in this gene may disrupt normal functioning in these airway cells, and make a child vulnerable to asthma.”
Klaus Bønnelykke, Patrick Sleiman, Kasper Nielsen, Eskil Kreiner-Møller, Josep M Mercader, Danielle Belgrave, Herman T den Dekker, Anders Husby, Astrid Sevelsted, Grissel Faura-Tellez, Li Juel Mortensen, Lavinia Paternoster, Richard Flaaten, Anne Mølgaard, David E Smart, Philip F Thomsen, Morten A Rasmussen, Silvia Bonàs-Guarch, Claus Holst, Ellen A Nohr, Rachita Yadav, Michael E March, Thomas Blicher, Peter M Lackie, Vincent W V Jaddoe, Angela Simpson, John W Holloway, Liesbeth Duijts, Adnan Custovic, Donna E Davies, David Torrents, Ramneek Gupta, Mads V Hollegaard, David M Hougaard, Hakon Hakonarson, Hans Bisgaard. A genome-wide association study identifies CDHR3 as a susceptibility locus for early childhood asthma with severe exacerbations. Nature Genetics, 2013; DOI: 10.1038/ng.2830