samples. This comprehensive quality control analysis was performed using the R BioConductor package ‘GenABEL'.34 The finally processed data set was from 149 livers (71 males and 78 females, Supplementary Table S1) and consisted of 299 352 SNPs and 15 439 gene expression levels. As a further internal control, we performed genotyping of sex chromosome-specific amelogenin gene variants35 and analysis of sex-specific gene expression (for example, XIST, RPS4Y, SMCY), which revealed 100% agreement with patient documentation.
