Why some people get really ill with flu while others just need a few days and no treatment to recover? Man flu aside, the answer may be in the IFITM3 gene, which apparently combats the illness and prevents its spread. An international team of researchers has found that people with low levels or a modified version of this gene are more likely to be sick and even to be killed by the disease.
The finding, published online in Nature, may explain why the 2009 pandemic flu affected people so differently, although there may be other factors in play as well. Researchers experimented on mice, finding that ‘mice lacking Ifitm3 display fulminant viral pneumonia when challenged with a normally low-pathogenicity influenza virus, mirroring the destruction inflicted by the highly pathogenic 1918 “Spanish” influenza’, as they write in their study.
In addition, they checked the presence of this gene in 53 hospitalized patients with flu, finding that three of them had a modified version of the gene that made them more vulnerable to the illness.
Though further research is needed, this information may be crucial in the event of a pandemic outbreak. Also, it could lead to the development of a drug to prevent the disease.
‘Our research is important for people who have this variant as we predict their immune defences could be weakened to some virus infections,’ says Professor Paul Kellam, from the Wellcome Trust Sanger Institute and co-author of the study. ‘Ultimately as we learn more about the genetics of susceptibility to viruses, then people can take informed precautions, such as vaccination to prevent infection.’
Photo: William Brawley
Everitt, A., Clare, S., Pertel, T., John, S., Wash, R., Smith, S., Chin, C., Feeley, E., Sims, J., Adams, D., Wise, H., Kane, L., Goulding, D., Digard, P., Anttila, V., Baillie, J., Walsh, T., Hume, D., Palotie, A., Xue, Y., Colonna, V., Tyler-Smith, C., Dunning, J., Gordon, S., The GenISIS Investigators, The MOSAIC Investigators, Rosalind L. Smyth, Peter J. Openshaw, Gordon Dougan, Abraham L. Brass, & Paul Kellam (2012). IFITM3 restricts the morbidity and mortality associated with influenza Nature DOI: 10.1038/nature10921