Separation of standards (A) and red blood cell metabolic extracts (B) by ionic chromatography. A) Standard metabolites profile was obtained by high performance ionic chromatography as described in Methods. Different colors refer to the different families of metabolites: blue: NAD(H) precursors; dark green: uridine derivatives; light green: cytidine derivatives; pink: inosine derivatives; purple: guanylic derivatives; red: adenylic derivatives; orange: AICAr derivatives and black: other detected metabolites. B) Representative chromatograms of red blood cells metabolic extracts from a control (black line) and a HRH patient (orange line). Insets represents zoom of the indicated regions. The Asterisk (ZTP inset) indicates an unidentified peak found in the control and that does not correspond to ZTP. The control and HRH extracts correspond to Control10 and HRH8 extracts (see Additional file 1: Table S1), respectively. A B, The red dashed line indicates the sodium acetate elution gradient. Nicotinamide (riboside) stands for the mix of nicotinamide and nicotinamide riboside, these two metabolites being not separated under our chromatographic conditions.