Figure 1: C allele at SNP 12252 associated with disease severity in acutely influenza A (H1N1)pdm/09 infected Chinese individuals.

(a) Allele frequencies were obtained from the 1,000 genomes project: allele frequencies vary significantly among different populations. (b) Allele frequencies obtained from Influenza A pH1N1/09 confirmed patients from Beijing You’an Hospital. (c) Proportion of mild versus severe flu patients carrying CC or CT/TT genotype with confirmed Influenza A pH1N1/09 infection from Beijing You’an Hospital.