Copenhagen: The gene types that normally double the risk of
asthma are neutralised when families with new-borns have a cat. This is
the result of a study from the Danish Pediatric Asthma Center conducted
by researchers at the University of Copenhagen, Herlev-Gentofte Hospital
and Næstved Hospital. The study has been published in the Journal of
Allergy and Clinical Immunology.
The time just before and after a child is born is vital to whether the child will develop asthma – and possibly other diseases. This is the result of research conducted by the Danish Pediatric Asthma Center, COPSAC, which is a collaboration between the University of Copenhagen and Herlev-Gentofte Hospital, among others, and headed by Clinical Professor Hans Bisgaard. More precisely, having a cat can be a deciding factor.
Hans Bisgaard is excited by the result. Not because the result can be translated into concrete treatment right away, but because the study shows that a disease gene in the human body is turned on and off depending on the immediate surroundings.
The results show that cats remove the increased risk of asthma among children with a specific variant of the 17q21 gene. The gene variant is the strongest known factor for whether a child will develop asthma. In addition, profound analyses of the researchers’ material show that cats do not just protect against asthma, but also against pneumonia and bronchitis among toddlers and children with this gene variant. This is linked up with the fact that the 17q21 gene is known to be involved in all three conditions.
Mapping Genes
Together with Næstved Hospital a group of researchers from the Danish Pediatric Asthma Center have examined data from 377 Danish children of mothers suffering from asthma.
The researchers have mapped the children’s genes and gathered data on the children’s surroundings throughout their childhood, among other things by taking samples from the children’s homes and by interviewing the parents.
‘What is special about the results is that they document the interaction between genetics and the environment – how a disease gene in the body can be turned on and off depending on the immediate surroundings’, says Jakob Stokholm, who is the principal author of the article published in the Journal of Allergy and Clinical Immunology.
Almost every third child in the study has the gene variant, just as many children of mothers with asthma have it.
Dogs Do Not Work
The study also shows that only cats can prevent the development of asthma. Having a dog does not affect the child’s genes.
‘We still do not know why cats may be able to prevent asthma among this group of children, while dogs do not. Perhaps cats bring home different bacteria than dogs, and these bacteria affect the immune system. Perhaps cats affect the bacteria communities in the body, e.g. in the bowels, which many research results link to our health’, says Jakob Stokholm.
‘Also we do not know how much cat is required – or whether it has to be a particular type of cat’, he continues.
Therefore, Jakob Stokholm explains, much more research is required before it makes sense to advice people to get a cat to prevent asthma. Especially because having a cat may also have health-related drawbacks. An older study also conducted by the Danish Pediatric Asthma Center shows that cats activate a gene that causes infantile eczema.
‘It will be interesting to take this research further. If we are able to explain why cats can affect the genes, it may in the long run enable us to show how we can prevent asthma among these high-risk children’, says Jakob Stokholm.
One of the next steps of the researchers at the Danish Pediatric Asthma Center is to study the children’s intestinal bacteria to look for more explanations or causes there.
Read the article in the Journal of Allergy and Clinical Immunology