Figure 3

Genome-wide linkage analysis CCL2, TNFα, and IFN-α production after H5N1 virus infection. QTL analysis (www.genenetwork.org) was performed on the CCL2 (A), TNFα (B), and IFN-α (C) cytokine concentrations in homogenates of lungs 48 hours after infection with HK213 H5N1 influenza virus. QTL associated with increased CCL2, TNFα, and IFN-α concentration after infection with HK213 virus (Qivr6.1) was identified on chromosome 6 (3.4 - 14.5 Mb) as indicated by an LRS score of more than 17.7 (pink horizontal line in QTL plot). A second QTL associated with increased TNFα concentrations was located on chromosome 1 (Qivr1, 154.5 - 160.6 Mb). This same locus also reached suggestive P-values for IFN-α. Suggestive loci were also found for CCL2 and TNFα on chromosome 6 (Qivr6.2, 81 - 89 Mb) and for IFN-α and CCL2 on chromosome 13 (Qivr13, 103.2 - 107.2 Mb. Pink line denotes significant linkage (genome-wide P <0.05, LRS >17.7) and grey line indicates suggestive linkage (LRS >12). For this study we focused on suggestive loci that were nearly significant and identified in two or more pro-inflammatory cytokine QTL analysis.