Danish researchers have found a gene that makes children susceptible to developing serious asthma early in life. The discovery may impact our understanding of how and why asthma develops. The findings have just been published in the Nature Genetics journal.
Asthma attacks are one of the most frequent causes of hospital admission for young children, but it is not yet fully understood why some children develop serious asthma in their early years. New research findings suggest that a particular gene variation may be part of the explanation.
It is known that asthma develops as a result of interplay between genetics and environment. Asthma is generally triggered by environmental influences, but genetics determined whether or not a child is susceptible to asthma. Together with a large international research team led by the Danish Paediatric Asthma Center at the University of Copenhagen, DTU researchers have therefore investigated whether children with serious asthma have gene variations which distinguish them from healthy children.
"We found a total of five DNA sequence variations which are overrepresented among children with asthma, compared to the control group. Four of these are already known in relation to asthma susceptibility, but we also found a variation in the CDHR3 gene which has not previously been associated with asthma," explains Kasper Nielsen, a PhD student at the Centre for Biological Sequence Analysis, DTU Systems Biology, who was responsible for analysing the genetic data.
The interesting thing about CDHR3 is that it is expressed in lung tissue, which makes a lot of sense in connection with asthma," says Kasper Nielsen.CDHR3 may therefore represent a new lead to follow when investigating what triggers asthma and how to prevent and treat asthma in children in the future.
The findings are based on a study of 1,200 Danish children aged 2 to 6 years who are listed in the Danish National Patient Register as having been admitted to hospital with serious acute asthma symptoms on more than two occasions, and a control group consisting of 2,500 Danes with no asthma. The analyses are based on the PKU blood sample taken from all Danish infants when they are about four days old.
"The strength of this study is that we have investigated a relatively small, but very specific subgroup of asthma patients. Asthma patients are generally a very heterogeneous group, whose symptoms can be caused by a wide variety of genetic and environmental factors. This makes it difficult to draw useful information from large gene association studies. Our results show that it is productive to focus on a small and very well-defined subgroup if you want to make important discoveries about the relationship between a particular phenotype and genes, in the hope of creating better treatment for patients in the future," concludes Kasper Nielsen.
Asthma means shortness of breath. It is a respiratory disorder that can affect people of all ages—children, adults and the elderly. The symptoms often manifest as bouts of coughing, breathlessness and wheezing. You can be genetically disposed to the disease, but beyond that the reasons some people get asthma are unknown.
For most sufferers, asthma is a chronic condition lasting many years. Some people grow out of the disease while others find themselves symptom-free and needing no medication for a period, after which their asthma returns. The new research findings indicate that more disease sub-type mapping is needed in order to improve future treatment and prevention options.
Source: Astma-Allergi Danmark and Klaus Bønnelykke, PhD, Danish Paediatric Asthma Center, University of Copenhagen.