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“Studies on the Chemical Nature of the Substance Inducing Transformation of Pneumococcal Types: Induction of Transformation by a Desoxyribonucleic Acid Fraction Isolated from Pneumococcus Type III” (1944) by Oswald Avery, Colin MacLeod and Maclyn McCarty

In 1944, Oswald Avery, Colin MacLeod, and Maclyn McCarty published an article in which they concluded that genes, or molecules that dictate how organisms develop, are made of deoxyribonucleic acid, or DNA. The article is titled “Studies on the Chemical Nature of the Substance Inducing Transformation of Pneumococcal Types: Induction of Transformation by a Desoxyribonucleic Acid Fraction Isolated from Pneumococcus Type III,” hereafter “Transformation.” The authors isolated, purified, and characterized genes within bacteria and found evidence that those genes were made of DNA and not protein.

Format: Articles

Subject: Publications

Madison Grant (1865–1937)

Madison Grant was a lawyer and wildlife conservationist who advocated for eugenics policies in the US during the late nineteenth and early twentieth centuries. In his 1916 book, The Passing of the Great Race; or, The Racial Basis of European History, Grant argued that what he called the Nordic race, which originated from northwest Europe, was biologically and culturally superior to all other people, including other Europeans.

Format: Articles

Subject: People

Mary Coffin Ware Dennett (1872-1947)

Mary Coffin Ware Dennett advocated for social reform in the United States in the early twentieth century, particularly regarding sex education and women's rights to access contraception. Dennett authored several publications on sex education and birth control laws. She also worked to repeal the Comstock Act, a federal law that made it illegal to distribute obscene materials through the US Postal Services.

Format: Articles

Subject: People, Reproduction

Infant Mortality: Results of a Field Study in Johnstown, PA., Based on Births in One Calendar Year (1915), by Emma Duke

The book Infant Mortality: Results of a Field Study in Johnstown, PA., Based on Births in One Calendar Year (1915), written by Emma Duke, detailed one of the first infant mortality field studies conducted by the US Children's Bureau. In the study, Duke and her colleagues collected information about over one thousand infants in the city of Johnstown, Pennsylvania. They used that information, along with interviews conducted with the families of the infants, to identify factors that affected infant mortality rates in the community.

Format: Articles

Subject: Experiments, Publications

The Inheritance of Acquired Characteristics (1924), by Paul Kammerer

The Inheritance of Acquired Characteristics is a book published in 1924, written by Paul Kammerer, who studied developmental biology in Vienna, Austria, in the early twentieth century. The Inheritance of Acquired Characteristics summarizes Kammerer's experiments, and explains their significance. In his book, Kammerer aims to explain how offspring inherit traits from their parents. Some scholars criticized Kammerer's reports and interpretations, arguing that they were inaccurate and misleading, while others supported Kammerer's work.

Format: Articles

Subject: Publications, Theories

David Starr Jordan (1851-1931)

David Starr Jordan studied fish and promoted eugenics in the US during the late nineteenth and early twentieth centuries. In his work, he embraced Charles Darwin s theory of evolution and described the importance of embryology in tracing phylogenic relationships. In 1891, he became the president of Stanford University in Stanford, California. Jordan condemned war and promoted conservationist causes for the California wilderness, and he advocated for the eugenic sterilization of thousands of Americans.

Format: Articles

Subject: People, Reproduction

"The linear arrangement of six sex-linked factors in drosophila, as shown by their mode of association” (1913), by Alfred Henry Sturtevant

In 1913, Alfred Henry Sturtevant published the results of experiments in which he showed how genes are arranged along a chromosome. Sturtevant performed those experiments as an undergraduate at Columbia University, in New York, New York, under the guidance of Nobel laureate Thomas Hunt Morgan. Sturtevant studied heredity using Drosophila, the common fruit fly. In his experiments, Sturtevant determined the relative positions of six genetic factors on a fly’s chromosome by creating a process called gene mapping.

Format: Articles

Subject: Experiments, Publications

Alfred Henry Sturtevant (1891–1970)

Alfred Henry Sturtevant studied heredity in fruit flies in the US throughout the twentieth century. From 1910 to 1928, Sturtevant worked in Thomas Hunt Morgan’s research lab in New York City, New York. Sturtevant, Morgan, and other researchers established that chromosomes play a role in the inheritance of traits. In 1913, as an undergraduate, Sturtevant created one of the earliest genetic maps of a fruit fly chromosome, which showed the relative positions of genes along the chromosome.

Format: Articles

Subject: People

Ignaz Philipp Semmelweis (1818-1865)

Ignaz Philipp Semmelweis demonstrated that the use of disinfectants could reduce the occurrence of puerperal fever in patients in nineteenth century Austria. Puerperal fever is a bacterial infection that can occur in the uterine tract of women after giving birth or undergoing an abortion. Semmelweis determined that puerperal fever is contagious and argued that the unhygienic practices of physicians, like examining patients after performing autopsies, caused the spread of puerperal fever.

Format: Articles

Subject: People

Simon Edward Fisher (1970-)

Simon Edward Fisher studied the genes that control speech and language in England and the Netherlands in the late twentieth and early twenty-first centuries. In 2001, Fisher co-discovered the FOXP2 gene with Cecilia Lai, a gene related to language acquisition in humans and vocalization in other mammals. When damaged, the human version of the gene leads to language disorders that disrupt language and speech skills. Fisher's discovery validated the hypothesis that genes influence language, resulting in further investigations of language disorders and their heritability.

Format: Articles

Subject: People

“A Linkage Between DNA Markers on the X Chromosome and Male Sexual Orientation” (1993), by Dean H. Hamer and Charles A. Thomas.

In 1993, Dean H. Hamer and colleagues in the US published results from their research that indicated that men with speicifc genes were more likely to be homosexual than were men without those genes. The study hypothesized that some X chromosomes contain a gene, Xq28, that increases the likelihood of an individual to be homosexual. Prior to those results, researchers had argued that the cause of homosexuality was environmental and that homosexuality could be altered or reversed. Hamer’s research suggested a possible genetic cause of homosexuality.

Format: Articles

Subject: Experiments

"Congenital Club Foot in the Human Fetus" (1980), by Ernesto Ippolito and Ignacio Ponseti

In 1980, Ernesto Ippolito and Ignacio Ponseti published their results on a histological study they performed on congenital club foot in human fetuses. The researchers examined the feet of four aborted fetuses and compared the skeletal tissues from healthy feet to those affected by congenital club foot. Infants born with club foot are born with one or both feet rigidly twisted inwards and upwards, making typical movement painful and challenging.

Format: Articles

Subject: Experiments

Walter Schiller (1887–1960)

Walter Schiller studied the causes of diseases in the US and Austria in the early twentieth century and in 1928, invented the Schiller test, or a way to diagnose early cervical cancer in women. Cervical cancer is the uncontrollable division of cells in the cervix, or lower part of the uterus. While living in Austria until his emigration to escape the Nazis in 1937, Schiller concluded that there was a form of cervical cancer, later named carcinoma in situ, that physicians could detect earlier than when tumors start to appear.

Format: Articles

Subject: People

John Hunter (1728–1793)

John Hunter studied human reproductive anatomy, and in eighteenth century England, performed one of the earliest described cases of artificial insemination. Hunter dissected thousands of animals and human cadavers to study the structures and functions of organ systems. Much of his anatomical studies focused on the circulatory, digestive, and reproductive systems. He helped to describe the exchange of blood between pregnant women and their fetuses. Hunter also housed various natural collections, as well as thousands of preserved specimens from greater than thirty years of anatomy work.

Format: Articles

Subject: People, Reproduction

Calvin Bridges’ Experiments on Nondisjunction as Evidence for the Chromosome Theory of Heredity (1913-1916)

From 1913 to 1916, Calvin Bridges performed experiments that indicated genes are found on chromosomes. His experiments were a part of his doctoral thesis advised by Thomas Hunt Morgan in New York, New York. In his experiments, Bridges studied Drosophila, the common fruit fly, and by doing so showed that a process called nondisjunction caused chromosomes, under some circumstances, to fail to separate when forming sperm and egg cells. Nondisjunction, as described by Bridges, caused sperm or egg cells to contain abnormal amounts of chromosomes.

Format: Articles

Subject: Experiments, Publications

Gardasil HPV Vaccination Series

In 2006, United States pharmaceutical company Merck released the Gardasil vaccination series, which protected recipients against four strains of Human Papillomaviruses, or HPV. HPV is a sexually transmitted infection which may be asymptomatic or cause symptoms such as genital warts, and is linked to cervical, vaginal, vulvar, anal, penile, head, neck, and face cancers.

Format: Articles

Subject: Technologies

The Arterial Switch Operation (1954-1975)

The arterial switch operation, also called the Jatene procedure, is an operation in which surgeons redirect the flow of blood through abnormal hearts. In 1975, Adib Jatene conducted the first successful arterial switch operation on a human infant. The arterial switch operation corrects a condition called transposition of the great arteries, abbreviated TGA, also called transposition of the great vessels, abbreviated TGV. TGA occurs when the pulmonary artery, which supplies deoxygenated blood to the lungs, and the aorta, which takes oxygenated blood to the body, are switched, or transposed.

Format: Articles

Subject: Technologies

The Apgar Score (1953-1958)

In 1952 Virginia Apgar, a physician at the Sloane Women’s Hospital in New York City, New York, created the Apgar score as a method of evaluating newborn infants’ health to determine if they required medical intervention. The score included five separate categories, including heart rate, breathing rate, reaction to stimuli, muscle activity, and color. An infant received a score from zero to two in each category, and those scores added up to the infant’s total score out of ten. An infant with a score of ten was healthy, and those with low scores required medical attention at birth.

Format: Articles

Subject: Technologies, Processes

"A Proposal for a New Method of Evaluation of the Newborn Infant" (1953), by Virginia Apgar

In 1953, Virginia Apgar published the article "A Proposal for a New Method for Evaluation of the Newborn Infant" about her method for scoring newborn infants directly after birth to assess their health and whether medical intervention was necessary. Apgar worked at the Presbyterian Hospital in New York City, New York, as an obstetrical anesthesiologist, a physician who administers pain medication during childbirth.

Format: Articles

Subject: Publications

Warren Tay (1843–1927)

The arterial switch operation, also called the Jatene procedure, is an operation in which surgeons redirect the flow of blood through abnormal hearts. In 1975, Adib Jatene conducted the first successful arterial switch operation on a human infant. The arterial switch operation corrects a condition called transposition of the great arteries, abbreviated TGA, also called transposition of the great vessels, abbreviated TGV. TGA occurs when the pulmonary artery, which supplies deoxygenated blood to the lungs, and the aorta, which takes oxygenated blood to the body, are switched, or transposed.

Format: Articles

Subject: Technologies

Sheldon Clark Reed (1910-2003)

Sheldon Clark Reed helped establish the profession of genetic counseling in the US during the twentieth century. In 1947 Reed coined the term genetic counseling to describe the interaction of a doctor explaining to a patient the likelihood of passing a certain trait to their offspring. With physicians being able to test for genetic abnormalities like cystic fibrosis, Reed helped trained individuals give patients the tools to make informed decisions. In 1955 Reed published the book Counseling in Medical Genetics.

Format: Articles

Subject: People

Sergio Cereceda Stone (1942- )

Sergio Cereceda Stone was born 16 April 1942 in the coastal city of Valparaiso, Chile. Stone's mother Luz was a housewife and caretaker for Sergio and his younger brother Lionel; his father Sergio served among the country's twenty appellate court judges. In the early 1950s Stone's father relocated the family to Santiago to further his law career.

Format: Articles

Subject: People, Ethics, Reproduction

Matthew Howard Kaufman (1942–2013)

Matthew Kaufman was a professor of anatomy at the University of Edinburgh, in Edinburgh, UK, who specialized in mouse anatomy, development, and embryology during the late twentieth century. According to the The Herald, he was the first, alongside his colleague Martin Evans, to isolate and culture embryonic stem cells. Researchers initially called those cells Evans-Kaufman cells. In 1992, Kaufman published The Atlas of Mouse Development, a book that included photographs of mice development and mice organs over time.

Format: Articles

Subject: People

Charles Otis Whitman (1842-1910)

Charles Otis Whitman was an extremely curious and driven researcher who was not content to limit himself to one field of expertise. Among the fields of study to which he made significant contributions were: embryology; morphology, or the form of living organisms and the relationships between their structures; natural history; and behavior.

Format: Articles

Subject: People

Gunther von Hagens (1945- )

Gunther von Hagens invented a plastination technique and created Body Worlds, a traveling exhibit that has made anatomy part of the public domain. Von Hagens invented the plastination technique in 1977 while working at Heidelberg University in Heidelberg, Germany. Von Hagen's plastination technique preserves real bodies and tissues by the removal of the fluid and replacement with resin. Body Worlds features three-dimensional, plastinated human bodies.

Format: Articles

Subject: People, Outreach, Reproduction