Barbar a McClintock 1902–1992
B
arbara McClintock, born Eleanor McClintock in
during the reproduction process. She developed the
Hartford, Connecticut, was an American scientist
technique for visualizing the maize chromosomes and,
who became one of the world’s most distinguished
using microscopic analysis, demonstrated many
cytogeneticists, studying the genetics of maize.
fundamental genetic processes during reproduction,
She developed her passion for information and science during high school and went on to study
including genetic recombination and how chromosomes exchange genetic information.
botany at Cornell University’s College of Agriculture.
She produced the first genetic map for maize,
An interest in genetics and the new field of cytology—
demonstrating that particular chromosome regions
the study of cell structure, function, and chemistry—
were responsible for creating a particular physical
led her to take the graduate genetics course at Cornell.
characteristic, and she demonstrated how the
And so began her life-long career in the development
recombination of chromosomes correlated with new
of maize cytogenetics and the study of the structure
characteristics. Until this time, the theory that genetic
and function of the cell, especially the chromosomes.
recombination could happen during meiosis (see p. 88)
She soon became recognized for her aptitude for,
was just that—a theory. She also showed how genes are
and thorough approach to, the subject. In her second
responsible for turning physical characteristics on or
year of graduate work, she improved on a method that
off, and developed theories to explain the repression
her supervisor was using and she was able to identify
or expression of genetic information from one
maize chromosomes. It was a problem he had been
generation of maize to the next.
working on for years! In her groundbreaking cytogenetic work, Barbara studied maize chromosomes and how they change
Unfortunately, Barbara was often thought of as being too independent and a bit of a “maverick,” not in keeping with most scientific institutes’ ideas of a “lady scientist.” As a result, she spent many years moving
Barbara McClintock was one of the world’s most distinguished cytogeneticists, renowned for her thorough approach and research.
from institute to institute, especially between Cornell and the University of Missouri. She even spent some time working in Germany. Because her work on gene regulation was conceptually difficult to understand, it was not always accepted by her contemporaries. She often described the reception of her research as “puzzlement, even hostility.” However, she was never deterred from continuing. In 1936, she was finally offered a faculty position at the University of Missouri and was Assistant Professor for five years until she realized that she would never be promoted. She left and worked for a summer at the Cold Spring Harbor Laboratory, finally accepting a
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