37¢ Barbara McClintock
Issue Date: May 4, 2005
City: New Haven, CT
Printed By: Banknote Corporation of America for Sennett Security Products
Printing Method: Lithographed
Perforations: Serpentine Die Cut 10.75
Barbara McClintock (1902-92), born in Hartford, Connecticut, earned B.S., M.S., and Ph.D. degrees in botany at Cornell University. She had wanted to study genetics, but women were not allowed to at that time.
Fellowships, however, enabled McClintock to pursue genetics at various institutions. In 1941, she was hired for one year at Carnegie Institute’s laboratory on Long Island, New York. There she bred and crossbred maize (corn) on a little plot of land near Long Island Sound.
“One year” stretched into 26 years of careful planting, pollination, and observation. In 1967, she retired from the Institute, but was invited to stay on as a researcher.
McClintock found that color changes in successive generations of maize were turned on or off by genetic “switches.” Moreover, these switches could move from one part of a chromosome to another. Her discovery was crucial to later genetic research.
More concerned with science than material comforts, McClintock lived in two rooms over a garage for 20 years. In 1981, when she was awarded a lifetime grant by the MacArthur Foundation, she finally moved into larger quarters. Two years later, at the age of 81, she became the first woman to receive an unshared Nobel Prize in Physiology or Medicine.