The daily ingestion of large amounts of mammalian liver (200 ± Gm. of prepared weight daily), together with a well balanced diet, has been shown by Minot and Murphy1 to benefit essentially all patients with pernicious anemia. Following this epoch-making discovery, Cohn and Minot and their associates2 prepared, by means of chemical fractionation, certain fractions of liver which were fed to patients with pernicious anemia. Minot and Murphy had previously accumulated data relative to the reticulocyte (young red blood cell) response and the rate of red blood cell formation in those patients fed liver. This knowledge therefore served as a means of eliminating ineffective fractions and of estimating the potency of active fractions. A water-soluble, nitrogenous, nonprotein extraction of liver, known as "fraction G," was obtained, a few grams of which were as effective in the treatment for pernicious anemia as were large quantities of whole liver.
In order to