Walter Stanborough Sutton (April 5, 1877 – November 10, 1916) was an American geneticist, cytologist, physician, and surgeon renowned for his pioneering work in establishing the chromosome theory of inheritance, which posits that chromosomes are the physical basis for transmitting hereditary traits.[1][2] Born in Utica, New York, as the fifth of seven sons to judge William B. Sutton and Agnes Black Sutton, he moved with his family to a farm in Russell County, Kansas, in 1887, where he developed an early interest in biology.[3][1]Sutton's academic journey began at the University of Kansas in 1896, initially in engineering before switching to biology; he earned a Bachelor of Arts in 1900 and a Master of Arts in zoology in 1901, with a thesis examining chromosome behavior during meiosis in grasshoppers.[3][1] He then pursued advanced studies at Columbia University from 1901 to 1907 under cytologist Edmund Beecher Wilson, earning an M.D. in 1907 while conducting research on cellular division.[2][1] During this period, Sutton focused on the grasshopper species Brachystola magna, observing that chromosomes segregate and assort independently during meiosis, mirroring Gregor Mendel's laws of inheritance.[2]His seminal publications—"On the Morphology of the Chromosome Group in Brachystola magna" (1902) and "The Chromosomes in Heredity" (1903), both in the Biological Bulletin—articulated the idea that chromosomes carry discrete units of heredity, independently co-developed with Theodor Boveri and forming the foundation of modern genetics.[4][5][1] After completing his medical training, including a surgical fellowship at Roosevelt Hospital in New York from 1907 to 1909, Sutton shifted to clinical practice, opening a surgical office in Kansas City, Missouri, in 1909 and joining the University of Kansas School of Medicine as an assistant professor of surgery, later promoted to associate professor in 1911.[3]In 1911, Sutton enlisted in the U.S. Army Medical Reserve Corps as a first lieutenant, and during