Shoukhrat Mitalipov and Masahito Tachibana’s Mitochondrial Gene Replacement in Primate Offspring and Embryonic Stem Cells (2009)

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The Debate over DNA Replication Before the Meselson-Stahl Experiment (1953–1957)

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David Hunter Hubel (1926–2013)

David Hunter Hubel (1926–2013)David Hunter Hubel studied the development of the visual system and how the brain processes visual information in the US during the twentieth century. He performed multiple experiments with kittens in which he sewed kitten’s eyes shut for varying periods of time and monitored their vision after reopening them. Hubel, along with colleague Torsten Wiesel, received the 1981 Nobel Prize in Physiology or Medicine for that research. By using kittens as models for human children and sewn eyes as models for congenital vision disorders, Hubel’s research demonstrated how vision impairments can affect the development of the visual system in humans. Furthermore, Hubel’s research has informed

Experiments on the Reproductive Costs of a Pure Capital Breeder, the Children’s Python (Antaresia childreni) (2013), by Olivier Lourdais, Sophie Lorioux, and Dale F. DeNardo

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“Of Pregnancy and Progeny” (1980), by Norbert Freinkel

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Ponseti's Treatment for Congenital Clubfoot (1963)

Ponseti's Treatment for Congenital Clubfoot (1963)In 1963, Ignacio Ponseti and Eugene Smoley experimentally determined an effective and minimally invasive method of treating congenital clubfoot. Congenital clubfoot is a disorder in which a newborn’s foot is rigidly turned inwards and upwards. During the early 1960s, orthopedists often relied on invasive surgical procedures to treat clubfoot. In Ponseti and Smoley’s experiment, Ponseti and Smoley had a team of physicians treat patients with clubfoot using the Ponseti method, which consisted of manually manipulating each patient’s foot into a more desirable position and subsequently casting each foot to heal in place. After following up with the patients for several years, Ponseti and Smoley concluded that the Ponseti method is an effective alternative to the more invasive surgical procedures that orthopedists had often

Roger Sperry’s Split Brain Experiments (1959–1968)

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"RNA-Guided Human Genome Engineering via Cas 9" (2013), by Prashant Mali, Luhan Yang, Kevin M. Esvelt, John Aach, Marc Guell, James E. DiCarlo, Julie E. Norville, and George M. Church

"RNA-Guided Human Genome Engineering via Cas 9" (2013), by Prashant Mali, Luhan Yang, Kevin M. Esvelt, John Aach, Marc Guell, James E. DiCarlo, Julie E. Norville, and George M. ChurchIn 2013, George Church and his colleagues at Harvard University in Cambridge, Massachusetts published "RNA-Guided Human Genome Engineering via Cas 9," in which they detailed their use of RNA-guided Cas 9 to genetically modify genes in human cells. Researchers use RNA-guided Cas 9 technology to modify the genetic information of organisms, DNA, by targeting specific sequences of DNA and subsequently replacing those targeted sequences with different DNA sequences. Church and his team used RNA-guided Cas 9 technology to edit

David Baltimore (1938– )

David Baltimore (1938– )David Baltimore studied viruses and the immune system in the US during the twentieth century. In 1975, Baltimore was awarded the Nobel Prize in Physiology or Medicine for discovering reverse transcriptase, the enzyme used to transfer information from RNA to DNA. The discovery of reverse transcriptase contradicted the central dogma of biology at the time, which stated that the transfer of information was unidirectional from DNA, RNA, to protein. Baltimore’s research on reverse transcriptase led to the discovery of retroviruses, which accelerated the development of treatments for human immunodeficiency virus or HIV and cancer vaccines. Baltimore also influenced public policy and opinion on genetic engineering. In 1975, he helped organize the Asilomar Conference in Pacific Grove, California, which discussed

Equilibrium Density Gradient Centrifugation in Cesium Chloride Solutions Developed by Matthew Meselson and Franklin Stahl

Equilibrium Density Gradient Centrifugation in Cesium Chloride Solutions Developed by Matthew Meselson and Franklin StahlMatthew Meselson, Franklin Stahl, and Jerome Vinograd, developed cesium chloride, or CsCl, density gradient centrifugation in the 1950s at the California Institute of Technology, or Caltech, in Pasadena, California. Density gradient centrifugation enables scientists to separate substances based on size, shape, and density. Meselson and Stahl invented a specific type of density gradient centrifugation, called isopycnic centrifugation that used a solution of cesium chloride to separate DNA molecules based on density alone.