Originally published as Genetics Published Articles Ahead of Print on May 4, 2007.

Genetics, Vol. 176, 1835-1844, July 2007, Copyright © 2007
doi:10.1534/genetics.107.073536

Interleukin 22 Is a Candidate Gene for Tmevp3, a Locus Controlling Theiler's Virus-Induced Neurological Diseases

F. Levillayer1, M. Mas2, F. Levi-Acobas, M. Brahic and J. F. Bureau3

Unité des Virus Lents, URA CNRS1930, Institut Pasteur, 75724 Paris Cedex 15, France

3 Corresponding author: Department of Virology, Pasteur Institute, 28 rue du Dr Roux, 75724 Paris Cedex 15, France.
E-mail: jfb{at}pasteur.fr

After intracerebral inoculation, Theiler's virus induces in its natural host, the mouse, an acute encephalomyelitis followed, in susceptible animals, by chronic inflammation and primary demyelination. Susceptibility to demyelination among strains of laboratory mice is explained by the capacity of the immune system to control viral load during persistence. Also, differences of susceptibility to viral load between the susceptible SJL strain and the resistant B10.S strain are mainly due to two loci, Tmevp2 and Tmevp3, located close to the Ifng locus on chromosome 10. In this article, we show that the Tmevp3 locus controls both mortality during the acute encephalomyelitis and viral load during persistence. Most probably, two genes located in the Tmevp3 interval control these two different phenotypes with efficiencies that depend on the age of the mouse at inoculation. Il22, a member of the IL-10 cytokine family, is a candidate gene for the control of mortality during the acute encephalomyelitis.