Washington D.C.: Turns out, asthma patients with a specific genetic profile exhibit more intense symptoms of asthma following exposure to vehicular pollution.
According to researchers at the National Institutes of Health, asthma patients who lack this specific genetic profile do not have the same sensitivity to vehicular pollution and do not experience worse asthma symptoms.
The scientists stated that the results were based on genetic variation, the subtle differences in DNA that make each person unique. They further added that to understand the concept, one should think of human genes, which are made up of DNA base pairs A, C, G, and T, as written instructions for making proteins.
"All humans have the same genes, in other words, the same basic instructions, but in some people, one DNA base pair has been changed. This common type of genetic variation is called a single nucleotide polymorphism or SNP, and it can alter the way proteins are made and make individuals more or less prone to illness," said Shepherd Schurman, lead author of the study.
The scientists examined four SNPs that are involved in a biochemical pathway which leads to inflammatory responses in the body. They explained that SNPs are usually studied one at a time, but they wanted to learn if different combinations of these SNPs, along with pollution exposure, could worsen symptoms in a person with an inflammatory disease like asthma.
Gathering information about the SNPs, severity of asthma symptoms, and residential addresses of 2,704 EPR participants with asthma, they used the data to divide the participants into three groups: hyper-responders, or those very sensitive to air pollution and likely to develop inflammation; hypo-responders, or those insensitive to air pollution and less likely to develop inflammation; and those in between.
The researchers found that asthma sufferers who were hyper-responders and lived closer to heavily travelled roads had the worst asthma symptoms, such as difficulty in breathing, chest pain, cough, and wheezing, compared to the other groups. In contrast, asthma patients who were hypo-responders and lived further away from busy roads had milder symptoms. They concluded the work could greatly enhance the quality of life for people with asthma.
The results emphasized the importance of gene-environment interactions in the progression of a disease.
The study appeared in the Journal of Scientific Reports.