Effect of Maternal Tobacco Smoke Exposure on the Placental Transcriptome

Hierarchical clustering analysis of women exposed to tobacco smoke and those without exposure according to 100 differentially expressed genes with the lowest P value. Each column represents a separate sample and each row a single gene. The relative gene expressions are expressed by a gradient intensity of color. The lightest red indicates the lowest expression and the lightest green indicates maximal expression. The color bar at the top of the heat map indicates women categorized for smoking status: red indicates smokers and blue indicates nonsmokers.

Gene expression of selected genes in controls and smokers detected by qRT-PCR. The values are expressed as 2−ΔΔCt and presented as the mean plus standard error. CTR-controls, SK-smokers, **p < 0.01.