The only the probe set representing the Cd14 gene (1417268_at) targeting the exon and 3’-UTR of the Cd14 gene in the Affymetrix M430 dataset was used. Cd14 expression varied widely among 67 BXD RI strains, with a fold-change of 1.84 (Fig 1). The strain with the highest level of expression (8.58±0.11) was BXD13, while the strain with the lowest expression (7.69±0.22) was BXD28. The heritability of Cd14 expression value was 0.323, which suggested that genetic factors contribute to variation in expression. This heritable variation enables us to identify genetic loci that influence expression of Cd14 in the BXD mice.
