Viruses come and go, but there are some that just seem to come back every year, like the adenovirus that causes the common cold.  Because it mutates so quickly, we’re infected by different adenoviruses each year.  Another common viral ailment is gastroenteritis, which can be caused by the astrovirus, norovirus or rotavirus.  Growing up, the “stomach flu” seemed to move through the members of our household annually.  When one person began to vomit, it was only a matter of time before the next victim fell, until everyone had been wiped out…..except my Dad.  He just never got the stomach flu!

This unique, and very desirable trait in my opinion, is most likely due to a genetic variation in my father’s immune system. Interestingly enough, it is believed that viruses have played an important role in the evolution of an estimated 139 genes that control susceptibility to viral infections. These genes have been influenced over thousands of years by exposure to different viruses, in different geographic locations.  The selective pressure created through exposure has led to the accumulation of many genes that give their hosts “protection” from certain viruses.

Understanding how these genes and their protein products function is useful!  Is it possible that they might play an important role in the development of better treatments for specific viral infections, some kind of gene therapy to prevent viral infections like a “gene vaccine”, or maybe even cures! Although I always admired his ability to resist the stomach flu, I now see him in a new light.  He’s living proof that these genes exist, and that variety really is the spice of life!

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