Embryo Project Encyclopedia Articles

Rosalyn Sussman Yalow co-developed the radioimmunoassay (RIA), a method used to measure minute biological compounds that cause immune systems to produce antibodies. Yalow and research partner Solomon A. Berson developed the RIA in the early 1950s at the Bronx Veterans Administration (VA) Hospital, in New York City, New York. Yalow and Berson's methods expanded scientific research, particularly in the medical field, and contributed to medical diagnostics. For this achievement, Yalow received the Nobel Prize in Physiology or Medicine in 1977. The RIA technique is used to measure more than one hundred biochemical substances, including infectious agents, narcotics, and hormones, such as those used to diagnose infertility and hypothyroidism.

In 2015, biologist Helena D. Zomer and colleagues published the review article “Mesenchymal and Induced Pluripotent Stem Cells: General Insights and Clinical Perspectives” or “Mesenchymal and Induced Pluripotent Stem Cells” in Stem Cells and Cloning: Advances and Applications. The authors reviewed the biology of three types of pluripotent stem cells, embryonic stem cells, or ESCs, mesenchymal stem cells, or MSCs, and induced pluripotent stem cells, or iPS cells. Pluripotent stem cells are a special cell type that can give rise to other types of cells and are essential for development. The authors describe the strengths and weaknesses of each type of stem cell for regenerative medicine applications. They state that both MSC and iPS types of stem cells have the potential to regenerate tissues among many other therapeutic possibilities. In their article, Zomer and colleagues review the potential for MSCs and iPS cells to reshape the field of regenerative and personal medicine.

The goal of this research project was to examine how different messaging techniques, and especially expressions of emotionality surrounding the loss and recovery of biodiversity, can differently influence public attitudes about conservation and the environment. This question was explored using the case of de-extinction, an emerging and controversial conservation technology. De-extinction claims to “resurrect” extinct species, challenging widely held notions of extinction as permanent. Yet seeing extinction as reversible may shift how people feel about biodiversity loss and our moral responsibility to stop it.

Jérôme Lejeune was a French physician and researcher who studied genetics and developmental disorders. According to the Jérôme Lejeune Foundation, in 1958, Lejeune discovered that the existence of an extra twenty-first chromosome, a condition called Trisomy 21, causes Down Syndrome. Down Syndrome is a condition present in an individual since birth and is characterized by physical and developmental anomalies such as small ears, a short neck, heart defects, and short height as children and adults. Throughout his career, Lejeune also discovered that other developmental disorders, such as cri du chat (cry of the cat) syndrome, were caused by chromosomal abnormalities. Lejeune also used his influence in the scientific community to promote pro-life beliefs, and often met with Pope John Paul II to discuss ethical dilemmas such as abortion of fetuses after detection of chromosomal abnormalities. Lejeune was one of the first researchers to link chromosomal abnormalities to developmental disorders with his discovery of Trisomy 21, leading future researchers to identify more links between the two.

George Otto Gey was a scientist in the US who studied cells and cultivated the first continuous human cell line in 1951. Gey derived the cells for that cell line, called the HeLa cell line, from a woman called Henrietta Lacks, a Black woman who had cervical cancer. Cell lines are a cluster of cells that continuously multiply on their own outside of the organism from which they originated. Gey developed new techniques for in vitro, or laboratory-based, maintenance of organs and hormonal tissue, created new methods for cell cultivation, and researched nutritional media, or cell food. Much of his research involved tissue culture, which is the process by which cells are grown under controlled conditions. He also founded what is now known as the Tissue Culture Association, or the TCA, which centered around furthering laboratory research around tissue culturing. By introducing new techniques and methods to cultivate human cells, Gey expanded the laboratory techniques around cell cultivation and helped contribute to a deeper understanding of the human body for future scientific research.

John Langdon Down studied medicine in England in the nineteenth century and was one of the first people to develop a complete description of the disorder that would later be known as Trisomy 21, or Down Syndrome. Down Syndrome is a condition caused by the presence of an extra chromosome, which may cause a person to be born with certain impaired learning abilities and physical features such as a short neck, flattened face, and almond-shaped eyes. In 1866, Down published one of the first accounts to accurately describe people with Down Syndrome, or what he called “Mongolism,” and identify it as a distinct condition. Additionally, Down advocated for people with mental disabilities at a time when their families commonly abandoned them and medical professionals did not prioritize them. He improved the quality of care for people in the centers he worked in and increased their educational opportunities so they would be better prepared to live a normal life. Down brought increased attention to Down Syndrome, leading to the future discovery of the chromosomal anomaly that causes the disorder, and promoting a higher standard of care for people with mental disabilities.

In the United States, most people are assigned both a biological sex and gender at birth based on their chromosomes and reproductive organs. However, there is an important distinction between biological sex and gender. Biological sex, such as male, female, or intersex, commonly refers to physical characteristics. Gender refers to the socially constructed roles, behaviors, and actions people take on, usually in relation to expectations of masculinity or femininity. As of 2022, there is disagreement over the relation between sex and gender. People’s biological sex and gender greatly influence the way they understand themselves, as well as how others treat them and how they interact with society. Moreover, some people’s gender differs from what they were assigned at birth, and they face discrimination, harassment, and violence. Evolving understandings of gender and sex in the US have created more ways for people to live and express their gender identities.

In his 1991 article Screening for Congenital Hypothyroidism, Delbert A. Fisher in the US reported on the implementation and impact of mass neonatal screening programs for congenital hypothyroidism (CH) from the early 1970s through 1991. CH is a condition that causes stunted mental and physical development in newborns unless treatment begins within the first three months of the newborn's life. In the early 1970s, regions in Canada and the US had implemented screening programs to diagnose and treat CH as quickly as possible after the infant's birth. By 1991 many other countries had adopted the early screening program, and Fisher estimated that 10 to 12 million newborns per year were tested in the early 1990s. The screening programs, along with physician education and improved screening techniques, such as radioimmunoassay, helped significantly reduce the incidence of abnormal newborn development resulting from untreated congenital hypothyroidism.

Solomon A. Berson helped develop the radioimmunoassay (RIA) technique in the US during the twentieth century. Berson made many scientific contributions while working with research partner Rosalyn Yalow at the Bronx Veterans Administration (VA) hospital, in New York City, New York. In the more than twenty years that Berson and Yalow collaborated, they refined the procedures for tracing diagnostic biological compounds using isotope labels. In the late 1950s they developed the RIA based on the ability to trace the competition between and ligands, or small molecules that bind to specific sites of other biomolecules, and proteins for the same molecular binding site, a process called competitive binding. Scientists widely used Berson and Yalow's RIA, as these methods permit the use of a minimal sample of blood for accurate measurements of biological molecules such as hormones that cause the production of antibodies. Berson and Yalow's research has advanced the study of physiology, including that of the reproductive system, with particular applications to the diagnosis and treatment of infertility.