Rosalyn S. Yalow, a medical physicist who persisted in entering a field largely reserved for men to become only the second woman to earn a Nobel Prize in Medicine, died on Monday in the Bronx, where she had lived most of her life. She was 89.
Her son, Benjamin Yalow, confirmed her death.
Dr. Yalow, a product of New York City schools and the daughter of parents who never finished high school, graduated magna cum laude from Hunter College in New York at the age of 19 and was the college’s first physics major. Yet she struggled to be accepted for graduate studies. In one instance, a skeptical Midwestern university wrote: “She is from New York. She is Jewish. She is a woman.”
Undeterred, she went on to carve out a renowned career in medical research, largely at a Bronx veterans hospital, and in the 1950s became a co-discoverer of the radioimmunoassay, an extremely sensitive way to measure insulin and other hormones in the blood. The technique invigorated the field of endrocrinology, making possible major advances in diabetes research and in diagnosing and treating hormonal problems related to growth, thyroid function and fertility.
The test is used, for example, to prevent mental retardation in babies with underactive thyroid glands. No symptoms are present until a baby is more than 3 months old, too late to prevent brain damage. But a few drops of blood from a pinprick on the newborn’s heel can be analyzed with radioimmunoassay to identify babies at risk.
The technique “brought a revolution in biological and medical research,” the Karolinska Institute in Sweden said in awarding Dr. Yalow the Nobel Prize in Physiology or Medicine in 1977.
“We are witnessing the birth of a new era of endocrinology, one that started with Yalow,” the institute said.
Dr. Yalow developed radioimmunoassay with her longtime collaborator, Dr. Solomon A. Berson. Their work challenged what was then accepted wisdom about the immune system; skeptical medical journals initially refused to publish their findings unless they were modified.
Dr. Berson died in 1972, before Dr. Yalow was honored with the Nobel. The institute does not make awards posthumously. Dr. Yalow was the second woman to win the Nobel Prize in Physiology or Medicine. The first, in 1947, was Gerty Theresa Cori, an American born in Prague. Dr. Yalow shared her Nobel with two other scientists for unrelated research. (Eight more women have won the medicine prize since then.)
Rosalyn Sussman was born in the South Bronx on July 19, 1921. Her father, Simon Sussman, who had moved from the Lower East Side of Manhattan to the Bronx, was a wholesaler of packaging materials; her mother, the former Clara Zipper, who was born in Germany, was a homemaker.
Dr. Yalow told interviewers that she had known from the time she was 8 years old that she wanted to be a scientist in an era when women were all but prohibited from science careers. She loved the logic of science and its ability to explain the natural world, she said.
At Walton High School in the Bronx, she wrote, a “great” teacher had excited her interest in chemistry. (She was one of two Walton graduates, both women, to earn a Nobel in medicine, the other being Gertrude Elion, in 1988. Walton was closed in 2008 as a failing school.) Her interests gravitated to physics after she read Eve Curie’s 1937 biography of her mother, Marie Curie, a two-time Nobel laureate for her research on radioactivity.
Nuclear physics “was the most exciting field in the world,” Dr. Yalow wrote in her official Nobel autobiography. “It seemed as if every major experiment brought a Nobel Prize.”
She went on to Hunter College, becoming its first physics major and graduating with high honors at only 19. After she applied to Purdue University for a graduate assistantship to study physics, the university wrote back to her professor: “She is from New York. She is Jewish. She is a woman. If you can guarantee her a job afterward, we’ll give her an assistantship.”
No guarantee was possible, and the rejection hurt, Dr. Yalow told an interviewer. “They told me that as a woman, I’d never get into graduate school in physics,” she said, “so they got me a job as a secretary at the College of Physicians and Surgeons and promised that, if I were a good girl, I would take courses there.” The college is part of Columbia University.
World War II and the draft were creating academic opportunities for women; to her delight, Dr. Yalow was awarded a teaching assistantship at the College of Engineering at the University of Illinois. She tore up her steno books and headed to Champaign-Urbana, becoming the first woman to join the engineering school’s faculty in 24 years.
As the only woman among 400 teaching fellows and faculty members, however, she faced more than the usual pressure to prove herself. When she received an A-minus in one laboratory course, the chairman of the physics department at Illinois said the grade confirmed that women could not excel at lab work; the slight fueled her determination.
She married a fellow graduate student, Aaron Yalow, in 1943. He died in 1992. Besides her son, Benjamin, of the Bronx, she is survived by her daughter, Elanna Yalow of Larkspur, Calif., and two grandchildren.
Dr. Yalow received her doctorate in nuclear physics in 1945, and went to teach at Hunter College the following year. When she could not find a research position, she volunteered to work in a medical lab at Columbia University, where she was introduced to the new field of radiotherapy. She moved to the Bronx Veterans Administration Hospital, now the James J. Peters Veterans Affairs Medical Center, as a part-time researcher in 1947 and began working full time in 1950. That same year, she began her 22-year collaboration with Dr. Berson.
Dr. Berson was seen as the dominant partner. By virtue of his gender and medical degree, he had more contacts with journals, professional societies and in academia. Dr. Yalow was single-mindedly focused on her research; for much of her professional life, she lived in a modest house in the Bronx less than one mile from the hospital. She had no hobbies and traveled only to give lectures and attend conferences.
In their work on radioimmunoassay, Dr. Yalow and Dr. Berson used radioactive tracers to measure hormones that were otherwise difficult or impossible to detect because they occur in extremely low concentrations. They went on to use the test to measure concentrations of vitamins, viruses and other substances in the body. Today the test has been largely supplanted by a technique that does not use radioactivity.
Their early work met with resistance. Scientific journals initially refused to publish their discovery of insulin antibodies, a finding fundamental to radioimmunoassay. The discovery, in 1956, challenged the accepted understanding of the immune system; few scientists believed antibodies could recognize a molecule as small as insulin. Dr. Yalow and Dr. Berson had to delete a reference to antibodies before The Journal of Clinical Investigation accepted their paper, and Dr. Yalow did not forget the incident; she included the rejection letter as an exhibit in her Nobel lecture.
With Dr. Berson, Dr. Yalow made other discoveries. Using radioimmunoassay, she determined that people with Type 2 diabetes produced more insulin than non-diabetics, providing early evidence that an inability to use insulin caused diabetes. Researchers in her lab at the Bronx veterans hospital modified radioimmunoassay to detect other hormones, vitamin B12 and the hepatitis B virus. The latter adaptation allowed blood banks to screen donated blood for the virus.
Dr. Berson’s death affected Dr. Yalow deeply; she named her lab in his honor so his name would continue to appear on her published research.
She was elected to the National Academy of Sciences in 1975 and received the Albert Lasker Medical Research Award, often a precursor to the Nobel, in 1976. At her death, she was senior medical investigator emeritus at the Bronx veterans medical center and the Solomon A. Berson distinguished professor-at-large at Mount Sinai School of Medicine in New York.
Five years after she received the Nobel, Dr. Yalow spoke to a group of schoolchildren about the challenges and opportunities of a life in science. “Initially, new ideas are rejected,” she told the youngsters. “Later they become dogma, if you’re right. And if you’re really lucky you can publish your rejections as part of your Nobel presentation.”