The research was published online on the American Thoracic Society's journal Web site ahead of the print edition of the American Journal of Respiratory and Critical Care Medicine.
"We found that the interaction between environmental mold exposure and certain variants of chitinase genes were positively associated with severe asthma exacerbations requiring hospitalization," said lead researcher, Ann Wu, assistant professor at the at Harvard Medical School and Harvard Pilgrim Health Care Institute.
Chitinases break down chitin, a component in many fungi, and are induced during allergic inflammation. It has been suggested by past research that these could be biomarkers of inflammation. Moreover, certain variants of chitinase genes are known to be expressed more heavily in people with asthma.
The researchers used data from the Childhood Asthma Management Program, a multicenter trial that enrolled children between the ages of 5 and 12 with mild to moderate persistent asthma. Mold measures were taken in the subjects' homes at the beginning of the study, and homes were classified as having greater or less than 25,000 mold colonies per gram of household dust.
"This level of mold in dust is high for a residential environment. However, it is not likely to be easily recognized. Studies have shown that homes that have problems with dampness (e.g. visible mold on walls/ceilings, water collection in basement, etc.) have higher levels of mold, but there is no specific level that is currently accepted to 'cause' problems," said Dr. Wu.
Finally, using blood samples, the researchers genotyped all the single nucleotide polymorphisms—SNPs, or variants in which just a single "letter" of the DNA code in a given gene is different—of chitinase genes and a chitinase-like gene within the study population.
They then analyzed the appearance of different variations of chitinase genes with level of mold exposure and number of hospital visits from severe asthma exacerbations. They found that certain variants of the chitinase gene CHIT1, in conjunction with high mold exposure, were associated with increased risk of severe asthma attacks.
"Our results support increasing evidence that CHIT1, which is primarily expressed in the lung, plays an important role in the pathophysiology of asthma in the proper environmental context of exposure to chitin, which was approximated by mold levels," said Dr. Wu. "To our knowledge this was the first study to examine the effect of mold levels on the association of SNPs in the genes of both chitinases and chitinase-like proteins with asthma and allergy-related phenotypes."
Chitinases may play a role in future targets for asthma therapy. Inhibition of chitinase enzymatic activity has been demonstrated to prevent hyper-responsiveness and inflammation in mice. It is plausible, said Wu, that therapeutics designed to block chitinase enzyme activity may prevent hyper-responsiveness and inflammation related to asthma.
"Future research should focus on expanding and replicating these findings," she said. "The focus should be on mechanisms of chitinases and chitinase-like proteins in allergic inflammation. Additionally, finding other genes that may interact with mold exposure will also be important. We plan to find a population to replicate these findings. Additionally, we are preparing to perform a Genome-Wide Association Study in this same population to identify other genes that may interact with mold exposure."
Keely Savoie | EurekAlert!
WAKE-UP provides new treatment option for stroke patients | International study led by UKE
17.05.2018 | Universitätsklinikum Hamburg-Eppendorf
First form of therapy for childhood dementia CLN2 developed
25.04.2018 | Universitätsklinikum Hamburg-Eppendorf
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
23.05.2018 | Life Sciences
23.05.2018 | Life Sciences
23.05.2018 | Physics and Astronomy