Correlation of ABCG8 expression to the frequency of the polymorphism D19H in the Stuttgart cohort. The expression analysis was performed in human ileal mucosal biopsies. Values are given as means ± SEM. Significance between the subgroups was analysed with Mann–Whitney U-test (nonparametric, two-tailed). P-values <0.05 were considered as statistically significant. (A) Quantitative analysis of mRNA expression is calculated as copy numbers. (GG) = wild type individual; (Gc) = carrier of p.D19H. Controls: (GG) = 80 and (Gc) = 15; gallstone carriers: (GG) = 20 and (Gc) = 9. (B) Representative Western blot images of ABCG8 protein and villin in ileal mucosa of control individuals and gallstone carriers, with and without p.D19H. Protein content was determined by densitometric analysis. The data were normalized to villin, an epithelial marker protein. Controls: (GG) = 59 and (Gc) = 11; gallstone carriers: (GG) = 11 and (Gc) = 9.