68 Facts About Barbara McClintock


Barbara McClintock was an American scientist and cytogeneticist who was awarded the 1983 Nobel Prize in Physiology or Medicine.

FactSnippet No. 543,815

Barbara McClintock received her PhD in botany from Cornell University in 1927.

FactSnippet No. 543,816

Barbara McClintock's developed the technique for visualizing maize chromosomes and used microscopic analysis to demonstrate many fundamental genetic ideas.

FactSnippet No. 543,817

Barbara McClintock's produced the first genetic map for maize, linking regions of the chromosome to physical traits.

FactSnippet No. 543,818

Barbara McClintock's demonstrated the role of the telomere and centromere, regions of the chromosome that are important in the conservation of genetic information.

FactSnippet No. 543,819

Barbara McClintock's was recognized as among the best in the field, awarded prestigious fellowships, and elected a member of the National Academy of Sciences in 1944.

FactSnippet No. 543,820

Barbara McClintock's developed theories to explain the suppression and expression of genetic information from one generation of maize plants to the next.

FactSnippet No. 543,821

Barbara McClintock's research became well understood in the 1960s and 1970s, as other scientists confirmed the mechanisms of genetic change and protein expression that she had demonstrated in her maize research in the 1940s and 1950s.

FactSnippet No. 543,822

Barbara McClintock was born Eleanor McClintock on June 16, 1902, in Hartford, Connecticut, the third of four children born to homeopathic physician Thomas Henry McClintock and Sara Handy McClintock.

FactSnippet No. 543,823

Barbara McClintock was an independent child beginning at a very young age, a trait she later identified as her "capacity to be alone".

FactSnippet No. 543,824

Barbara McClintock's was close to her father, but had a difficult relationship with her mother, tension that began when she was young.

FactSnippet No. 543,825

Barbara McClintock family moved to Brooklyn in 1908 and Barbara McClintock completed her secondary education there at Erasmus Hall High School; she graduated early in 1919.

FactSnippet No. 543,826

Barbara McClintock's discovered her love of science and reaffirmed her solitary personality during high school.

FactSnippet No. 543,827

Barbara McClintock's wanted to continue her studies at Cornell University's College of Agriculture.

FactSnippet No. 543,828

Barbara McClintock was almost prevented from starting college, but her father allowed her to just before registration began, and she matriculated at Cornell in 1919.

FactSnippet No. 543,829

Barbara McClintock began her studies at Cornell's College of Agriculture in 1919.

FactSnippet No. 543,830

Barbara McClintock pointed to Hutchison's invitation as a catalyst for her interest in genetics: "Obviously, this telephone call cast the die for my future.

FactSnippet No. 543,831

Barbara McClintock's worked as a research assistant for Lowell Fitz Randolph and then for Lester W Sharp, both Cornell botanists.

FactSnippet No. 543,832

Barbara McClintock's developed a technique using carmine staining to visualize maize chromosomes, and showed for the first time the morphology of the 10 maize chromosomes.

FactSnippet No. 543,833

In 1930, Barbara McClintock was the first person to describe the cross-shaped interaction of homologous chromosomes during meiosis.

FactSnippet No. 543,834

Barbara McClintock published the first genetic map for maize in 1931, showing the order of three genes on maize chromosome 9.

FactSnippet No. 543,835

From this evidence, Barbara McClintock hypothesized that there must be a structure on the chromosome tip that would normally ensure stability.

FactSnippet No. 543,836

Barbara McClintock's showed that the loss of ring-chromosomes at meiosis caused variegation in maize foliage in generations subsequent to irradiation resulting from chromosomal deletion.

FactSnippet No. 543,837

Barbara McClintock received a fellowship from the Guggenheim Foundation that made possible six months of training in Germany during 1933 and 1934.

FactSnippet No. 543,838

Barbara McClintock's had planned to work with Curt Stern, who had demonstrated crossing-over in Drosophila just weeks after McClintock and Creighton had done so; however, Stern emigrated to the United States.

FactSnippet No. 543,839

Barbara McClintock's left Germany early amidst mounting political tension in Europe, and returned to Cornell, remaining there until 1936, when she accepted an Assistant Professorship offered to her by Lewis Stadler in the Department of Botany at the University of Missouri in Columbia.

FactSnippet No. 543,840

Barbara McClintock observed the breakage and fusion of chromosomes in irradiated maize cells.

FactSnippet No. 543,841

Barbara McClintock's was able to show that, in some plants, spontaneous chromosome breakage occurred in the cells of the endosperm.

FactSnippet No. 543,842

Barbara McClintock's recalled being excluded from faculty meetings, and was not made aware of positions available at other institutions.

FactSnippet No. 543,843

Barbara McClintock believed she would not gain tenure at Missouri, even though according to some accounts, she knew she would be offered a promotion from Missouri in the spring of 1942.

FactSnippet No. 543,844

Barbara McClintock's accepted a visiting Professorship at Columbia University, where her former Cornell colleague Marcus Rhoades was a professor.

FactSnippet No. 543,845

In December 1941, she was offered a research position by Milislav Demerec, the newly appointed acting director of the Carnegie Institution of Washington's Department of Genetics Cold Spring Harbor Laboratory; Barbara McClintock accepted his invitation despite her qualms and became a permanent member of the faculty.

FactSnippet No. 543,846

In 1944, in recognition of her prominence in the field of genetics during this period, Barbara McClintock was elected to the National Academy of Sciences—only the third woman to be elected.

FactSnippet No. 543,847

Barbara McClintock's successfully described the number of chromosomes, or karyotype, of N crassa and described the entire life cycle of the species.

FactSnippet No. 543,848

Barbara McClintock's identified two new dominant and interacting genetic loci that she named Dissociation and Activator (Ac).

FactSnippet No. 543,849

Barbara McClintock's found that the Dissociation did not just dissociate or cause the chromosome to break, it had a variety of effects on neighboring genes when the Activator was present, which included making certain stable mutations unstable.

FactSnippet No. 543,850

Barbara McClintock's observed the effects of the transposition of Ac and Ds by the changing patterns of coloration in maize kernels over generations of controlled crosses, and described the relationship between the two loci through intricate microscopic analysis.

FactSnippet No. 543,851

Barbara McClintock found that the transposition of Ds is determined by the number of Ac copies in the cell.

FactSnippet No. 543,852

Barbara McClintock's referred to Dissociation and Activator as "controlling units"—later, as "controlling elements"—to distinguish them from genes.

FactSnippet No. 543,853

Barbara McClintock's hypothesized that gene regulation could explain how complex multicellular organisms made of cells with identical genomes have cells of different function.

FactSnippet No. 543,854

Barbara McClintock's discovery challenged the concept of the genome as a static set of instructions passed between generations.

FactSnippet No. 543,855

Barbara McClintock's identified "families" of transposons, which did not interact with one another.

FactSnippet No. 543,856

Nevertheless, Barbara McClintock continued to develop her ideas on controlling elements.

FactSnippet No. 543,857

Barbara McClintock's published a paper in Genetics in 1953, where she presented all her statistical data, and undertook lecture tours to universities throughout the 1950s to speak about her work.

FactSnippet No. 543,858

In 1957, Barbara McClintock received funding from the National Academy of Sciences to start research on indigenous strains of maize in Central America and South America.

FactSnippet No. 543,859

Barbara McClintock's was interested in studying the evolution of maize through chromosomal changes, and being in South America would allow her to work on a larger scale.

FactSnippet No. 543,860

Barbara McClintock explored the chromosomal, morphological, and evolutionary characteristics of various races of maize.

FactSnippet No. 543,861

Barbara McClintock officially retired from her position at the Carnegie Institution in 1967, and was made a Distinguished Service Member of the Carnegie Institution of Washington.

FactSnippet No. 543,862

Barbara McClintock was widely credited with discovering transposition after other researchers finally discovered the process in bacteria, yeast, and bacteriophages in the late 1960s and early 1970s.

FactSnippet No. 543,863

Barbara McClintock understood the role of transposons in evolution and genome change well before other researchers grasped the concept.

FactSnippet No. 543,864

In 1947, Barbara McClintock received the Achievement Award from the American Association of University Women.

FactSnippet No. 543,865

Barbara McClintock's was elected a Fellow of the American Academy of Arts and Sciences in 1959.

FactSnippet No. 543,866

In 1967, Barbara McClintock was awarded the Kimber Genetics Award; three years later, she was given the National Medal of Science by Richard Nixon in 1970.

FactSnippet No. 543,867

Barbara McClintock's was the first woman to be awarded the National Medal of Science.

FactSnippet No. 543,868

Barbara McClintock's received the Louis and Bert Freedman Foundation Award and the Lewis S Rosensteil Award in 1978.

FactSnippet No. 543,869

Barbara McClintock's was compared to Gregor Mendel in terms of her scientific career by the Swedish Academy of Sciences when she was awarded the Prize.

FactSnippet No. 543,870

Barbara McClintock's was elected a Foreign Member of the Royal Society in 1989.

FactSnippet No. 543,871

Barbara McClintock received the Benjamin Franklin Medal for Distinguished Achievement in the Sciences of the American Philosophical Society in 1993.

FactSnippet No. 543,872

Barbara McClintock's was awarded 14 Honorary Doctor of Science degrees and an Honorary Doctor of Humane Letters.

FactSnippet No. 543,873

Barbara McClintock's remained a regular presence in the Cold Spring Harbor community, and gave talks on mobile genetic elements and the history of genetics research for the benefit of junior scientists.

FactSnippet No. 543,874

Barbara McClintock spent her later years, post Nobel Prize, as a key leader and researcher in the field at Cold Spring Harbor Laboratory on Long Island, New York.

FactSnippet No. 543,875

Barbara McClintock died of natural causes in Huntington, New York, on September 2, 1992, at the age of 90; she never married or had children.

FactSnippet No. 543,876

Keller argued that because Barbara McClintock felt like an outsider within her field, she was able to look at her scientific subjects from a perspective different from the dominant one leading to several important insights.

FactSnippet No. 543,877

For example, when Barbara McClintock presented her findings that the genetics of maize did not conform to Mendelian distributions, geneticist Sewall Wright expressed the belief that she did not understand the underlying mathematics of her work, a belief he had expressed towards other women at the time.

FactSnippet No. 543,878

Barbara McClintock's felt she had crossed a desert alone and no one had followed her.

FactSnippet No. 543,879

Barbara McClintock was featured in a 1989 four-stamp issue from Sweden which illustrated the work of eight Nobel Prize-winning geneticists.

FactSnippet No. 543,880

The character reminiscent of Barbara McClintock is a reclusive geneticist at the fictional laboratory, who makes the same discoveries as her factual counterpart.

FactSnippet No. 543,881

Judith Pratt wrote a play about Barbara McClintock, called MAIZE, which was read at Artemesia Theatre in Chicago in 2015, and was produced in Ithaca NY, the home of Cornell University, in February–March 2018.

FactSnippet No. 543,882