Geneticists are the biologists who study genetics, the science of genes, heredity, and variation of organisms. Americans are among the forerunners in the science of genetics which received a massive boost upon the establishment of the Genetics Society of America (GSA). One of the most prominent geneticists to have ever lived, Thomas Hunt Morgan made vital discoveries elucidating the role that the chromosome plays in heredity and won the Nobel Prize in Physiology or Medicine in 1933 for his seminal works. One of Morgan’s long time collaborators, Alfred Henry Sturtevant is credited to have constructed the first genetic map of a chromosome. George Wells Beadle, a prominent scientist in the field of genetics, collaborated with Edward Lawrie Tatum to discover the role of genes in regulating biochemical events within cells. While genetics was a predominantly male-oriented field in the early 20th century, gutsy woman scientist Barbara McClintock made a name for herself by performing significant research in the development of maize cytogenetics. She produced the first genetic map for maize, linking regions of the chromosome to physical traits. More recently human geneticist Mary-Claire King gained fame for her work in identifying breast cancer genes. This section provides you information about the life and works of famous American geneticists.