Though previous study showed that TNF-α -308 AG genotype was associated with the clearance of Hepatitis B virus and the infection of Helicobacter pylori cagA subtype infection [24, 25], our results failed to show the role of this locus in SARS-CoV infection and this conclusion agreed with that of Chong WP et al [26]. This evidence concerns the gene TNF and severe acute respiratory syndrome.