ATP/ADP ratio across the members of the ES cell panel. (A) The bar plot summarizes the results of HPLC determination of ATP/ADP ratio for replicates of Hdhex4/5/Hdhex4/5-null ES cells (dKO), expressed as a percentage of the parental wild-type ES cell ATP/ADP ratio, showing a trend (P = 0.057) toward increased ATP/ADP ratio in the absence of full-length huntingtin. All data points are included. (B) The bar plot summarizes the results of HPLC determination of ATP/ADP ratio for two biological replicates performed in duplicate for each member of the Hdh20/7, Hdh50/7, Hdh91/7 and Hdh111/7 knock-in ES series, expressed as a percentage of the Hdh20/7 ATP/ADP ratio, demonstrating a decrease with increasing CAG repeat length (Pearson's correlation coefficient P = 0.018). All data points are included.