The model assumed linear intercompartmental transfer of D2HG except for the influx from interstitial fluid – both in the glioma and normal cell compartments – to the intracellular compartment where Michaelis–Menten transport was assumed based on the likelihood D2HG was a substrate for NaDC3 (SLC13A3) (23, 24). The gene discussed is SLC13A3; the disease is glioma.