2023-05-15 08:00:00
Sometimes, from time to time, history gives us a genius capable of understanding issues for which the world is not yet ready. People who, with their courage and genius, managed to get ahead of their time to reveal some of life’s deepest secrets. One of those figures was Barbara McClintock, a scientist who dared to explore and reveal the hidden mysteries of genetics.
Barbara McClintock’s story begins in the town of Hartford, the capital of the state of Connecticut, in 1902. Daughter of a doctor, said to have a solitary and independent character, from a very young age she would show herself as a very alert girl, with an open mind and endowed with a natural inclination for science. Therefore, after finishing secondary education, he would not hesitate to enroll in botany at the Cornell University School of Agriculture, where he would graduate at the age of 21. It was during that time that she began to be interested in genetics at the hands of the geneticist C. B. Hutchisonwho promoted it in 1927 to obtain a doctorate in the specialties of genetics and botany.
During his graduate studies, McClintock he would start the job that would occupy his entire professional career: the chromosome analysis of maize. already very early, At just 28 years old, he first described the crossing over that takes place between homologous chromosomes during meiosis, that is, the genetic recombination that occurs during cell reproduction. Their results were collected in the article titled A Correlation of Cytological and Genetical Crossing-over in Zea mays that she and her colleague, the geneticist Harriet Creightonpublished in the PNAS magazine in 1931, and since then they became part of all the textbooks of the time.
Two years later, in 1933, he would receive a Guggenheim scholarship to study in Germany, however, this period of his academic life would be frustrated by the rise of Nazism, which is why he returned to the United States very soon.
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Everything seemed to indicate that a promising career awaited McClintock in his own country, however, upon his return he would find that Cornell University did not hire professors, so his research would be funded for two years, between 1934 and 1936, by the Rockefeller Foundation, until the latter was hired by the University of Missouri.
After 4 years in Missouri, and after considering the impossibility of continuing to grow professionally and academically, McClintock would move to New York in 1941 to work at the Laboratorio Cold Spring Harbor, where he spent the rest of his professional life. Here the researcher would continue her studies on genetic inheritance linked to chromosomes, however, very soon she would come across the discovery that would forever change her life, her academic career, and at the same time would revolutionize the field of genetics like no other discovery. had done so far.
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Since the beginning of his career, McClintock had focused on studying the maize genome, but what he discovered this time was that some of the genetic elements he had previously observed could change position on chromosomes to turn other genes on or off adjacent or related. It was the first evidence that genes, which until then were considered static, could, without knowing how, change position.
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McClintock in a new article published in 1950 under the title The origin and behavior of mutable loci in maize, referred to these -the jumping genes– as “controlling elements“, since they were shown to be capable of modulating -activating or deactivating- the expression of other genes. In turn, he suggested that these transposable genetic elements, today known in genetics as transposerswere responsible for new mutations in pigmentation or other characteristics that he observed in maize.
As we stated a few lines ago, McClintock’s work was ahead of its time. It was a novel work, the complexity of which aroused the suspicion and even the hostility of his contemporary scientific colleagues, who for the most part considered it too radical or simply ignored it. Even so, he continued researching, publishing and defending his work in papers and conferences until finally, partly due to the solitary face that characterized him and his own methodology of doing things, sometimes considered extravagant, he decided to stop publishing his results.
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However, a few years later, in 1957, McClintock received a new boost to his career by obtaining funding from the National Science Foundation and the Rockefeller Foundation to study the genetic diversity of maize in South America.
It would not be until a few years later, until the French geneticists Francois Jacob y Jacques Monod published a paper in 1961 on the genetic regulatory mechanisms of protein synthesis, that members of the scientific community began to take seriously and verify McClintock’s findings and she began to be justly recognized for her invaluable contributions to genetics.
Since then, McClintock was the subject of numerous awards and honors, among which the 1983 Nobel Prize in Physiology or Medicine stands out. She was, in fact, the seventh woman to receive the award, however, the first to do so without having to share it with any other person. another researcher, a relatively extraordinary event in the history of the Nobel.
His life would continue for another decade, during which he continued to investigate until he went out on September 2, 1992. His discoveries forever revolutionized the field of genetic engineering, and have led to important advances in molecular biology, opening the door for scientists to better understand how genetic traits are passed from one generation to the next and how mutations can occur. In addition, their findings laid the foundation for the creation of genetic manipulation techniques such as the current CrisPR-Cas9, which allows scientists to cut and paste DNA with a precision never seen before. In short, it can be said that Barbara’s legacy McClintock has contributed to a better understanding of the complexity and diversity of life on Earth.
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