Janet Davison Rowley was an American human geneticist and the first scientist to identify a chromosomal translocation as the cause of leukemia and other cancers. Dr. Janet Davison Rowley is the first scientist to identify a chromosomal translocation as the cause of leukemia and other cancers. Janet Davison was born in New York City on April 5, 1925. Dr. Rowley, who was awarded the nation’s highest civilian honor, the Presidential Medal of Freedom, in 2009, was a part-time researcher who often worked at her dining room table in the early years of her career. She made her first landmark discoveries in 1972, when she became the first scientist to find evidence that alterations in chromosomes could lead to forms of leukemia and other kinds of cancer. He received the National Of Science in 1998.