George Minot

George Minot (1885-1950), American physician and hematologist (a blood specialist), who won the 1934 Nobel Prize in physiology or medicine for his contribution to the development of an effective therapy for pernicious anemia. This disorder, in which the bone marrow fails to produce mature, oxygen-carrying red blood cells, was fatal when Minot and his fellow researchers, American physicians William Parry Murphy and George Hoyt Whipple pioneered their treatment. Together, they discovered that feeding patients liver cured the disease.

Born in Boston, Massachusetts, George Richards Minot graduated from Harvard University in 1908, earning his medical degree there in 1912. After spending two years as a research assistant at the Johns Hopkins School of Medicine, Minot joined the faculty of the Harvard Medical School in 1915.

As a medical intern at the Massachusetts General Hospital in 1912, Minot first became interested in the possible link between diet and pernicious anemia. By studying blood samples under a microscope, Minot observed that young red blood cells, known as reticulocytes, seemed to thrive in the blood of anemic patients during the periods when their anemia was in remission. Since he knew that blood cells developed in the bone marrow, he concluded that pernicious anemia involved the bone marrow. Minot believed that diet had an effect on whether the young blood cells would mature. But Minot was unable to pursue his research for another decade. By then, he had learned of the experiments of George Hoyt Whipple in Rochester, New York, who had cured anemia in dogs by feeding them liver.

In 1925, Minot and Murphy began experiments in which they fed liver—as much as a half a pound a day—to patients with pernicious anemia. The number of the patients' reticulocytes increased dramatically, usually within two weeks. Minot first announced the successful results of this form of treatment in 1926. Subsequently, pharmaceutical companies developed extracts of liver that could be taken internally or injected, so patients no longer had to eat large quantities of liver. In the late 1940s, researchers learned that pernicious anemia was caused by an inability to absorb vitamin B₁₂, which is the substance in liver that causes reticulocytes to be formed.