A gene variant has been discovered and linked to an increased
risk of severe childhood asthma. Researchers suggest that a faulty version of the
gene CDHR3 may even be the direct cause of the disease in some children.
CDHR3 is active in the epithelial cells that line the inner
surface of the airways.
'Abnormalities in the epithelial cells may increase a patient's
risk to environmental triggers by exaggerating immune responses and making the
airway overreact', explained Dr Hakonarson. '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'.
Using information from the Danish national health registries,
researchers identified 1,173 cases of severe recurrent asthma in children aged
two to six. Then, thanks to the Danish Neonatal Screening Biobank they were
able to compare the children's genomes against 2,522 healthy controls.
The study, published in Nature Genetics, also confirms the association
of four other genes that had previously been linked to asthma. The team replicated
its findings using the DNA and medical data from a separate sample of children
of European and non-European ancestry.
The researchers say they will continue to investigate how the
CDHR3 gene variant might increase susceptibility to asthma. Ultimately, they
hope to develop treatments for asthma that target the CDHR3 gene variant or the
biological pathway it feeds into.
'There will be a subset of people with asthma, between 15 and
20 percent, where this gene has the biggest impact on their condition', said Dr