Genes Explain Why You Catch the Flu

(Ivanhoe Newswire) -- Ever wonder why some people catch the flu and others do not? In a new study, investigators used genomics to answer this question.

"We looked at over 22,000 genes in 267 blood samples," Alfred Hero, professor at the University of Michigan College of Engineering, was quoted as saying. "No study of this magnitude has ever been done on human immune response."

The researchers inoculated 17 healthy participants with the flu virus, and about half of them got sick. They then collected gene expression data from each person at 16 time points over 132 hours. These data provided a clear picture of the gene expression over time in the people who developed flu symptoms and those who didn't.

Results showed whether a person gets sick or not comes down to a his/her immune system. The researchers were able to uncover the genomic signatures associated with immune response and flu symptoms.

The inflammatory genomic signature that differentiated the well group from the sick group was measurable up to 36 hours before the peak flu symptoms developed, suggesting it may be possible to detect illness early and allow patients to take precautions. The scientists hope that if they can understand what happens at the genome level, they could develop therapies to prevent the illness in the future.

SOURCE: PLoS Genetics, August 29, 2011