Viral gastroenteritis, or "stomach flu" is not actually a flu at all. It is most widely caused by a group of viruses called noroviruses. These viruses are highly contagious and casue a group of unpleasant symptoms, which include; abdominal pain, vomiting, and diarrhea. Outbreaks of these noroviruses spread quickly from individual to individual, especially in confined spaces. This has given the viruses the nickname of "cruise ship disease." Good hygiene can help prevent the spread of these viruses. Though there are many forms of noroviruses, one genetic variant in humans gives the individual resistance to the most common strain.
Genetic Resistance Edit
Norovirus resistance is highly heritable, with just two copies of the A version of the SNP being required for resistance. With two copies of the A version of the SNP, the individual lacks a functioning version of the FUT2 gene. Though the absence of this functioning gene does not make the individual completely resistant to all forms of the noroviruses, they will most likely exhibit resistance to the most common strain of the virus. This is a form of recessive resistance, since two copies of the 'A' from of the SNP are needed for resistance, while 'AG' and 'GG' genotypes cause the individual to be susceptible to the most common strain of the norovirus.
FUT2 Gene Edit
Th FUT2 gene encodes for an enzyme. This enzyme modifies cell surface molecules to express the enzyme or release it into bodily fluids. With a nonfunctioning form of this gene the individual is unable to secrete the enzyme. Being a "non-secretor" has also been linked to resistance of other infections, while there is some data suggesting that these individuals are at higher risk for infections such as E. coli and the flu.
Personal Implications Edit
While the absense of a working copy of the FUT2 gene may give the indivudual resistance to the most common form of the norovirus, it does not prevent infection from all norovirus strains. Also with a possible increased risk for E. coli and the flu, it is still important to take precautions to prevent infections. This includes practicing good hygeine, precautions when handling and consuming raw food, and avoiding interactions with peolpe who may be suffering from an infection.
- Traits: Norovirus Resistance. (2014, September 14). Retrieved September 14, 2014.