Sanger sequencing is a laboratory method that scientists use to determine the sequence of nucleotides within a piece of deoxyribonucleic acid, or DNA. Frederick Sanger, who studied biochemistry in the United Kingdom, and colleagues developed the technique in 1977. Sanger sequencing was one of the first methods to sequence long stretches of DNA accurately, allowing researchers to collect and analyze large amounts of genetic data. The technique uses modified nucleotides that terminate DNA synthesis at specific points, which results in fragments of varying lengths that researchers sort to determine the sequence of nucleotides. Sanger sequencing was one of the most widely used sequencing methods for thirty years after its creation and facilitated early genomic sequencing projects, such as the Human Genome Project, or HGP. As of 2025, Sanger sequencing remains a common technique despite the advent of newer sequencing technologies and plays a role in clinical settings and genetic counseling, a service that provides information on genetic conditions to people and their families.

Charles Rotimi is a researcher who studies the etiology of complex diseases and health disparities and advocates for the inclusion of greater racial and ethnic diversity in genomic repositories. In the early 2000s, Rotimi spearheaded the recruiting of African communities for participation in the International HapMap Project. As director of the Center for Research on Genomics and Global Health, or CRGGH, at the National Institutes of Health, or NIH, Rotimi led governmental research on human genetic variation and patterns of disease. Rotimi is a founding member of the Human Heredity and Health in Africa, or H3Africa, initiative, which aims to increase the representation of African populations in global genetic studies. Through his epidemiological research, leadership in advocacy groups for the support of African scientists, and his collaboration in genomic diversity initiatives, Rotimi promotes racial and ethnic representation in genetic research, especially regarding the inclusion of African people and the African diaspora.

Luigi Luca Cavalli-Sforza (1922–2018) was a researcher whose work explored the relationships between human genetic diversity and historical migrations, integrating genetics and anthropology to determine how humans populated the world. Prior to his work in human genetics, Cavalli-Sforza studied genetic recombination in bacteria and helped determine the system of genetic inheritance within Escherichia coli in the late 1940s. After pivoting his research focus and assuming a long-term teaching and research position at Stanford University in Stanford, California, in 1971, Cavalli-Sforza participated in studies that modeled human migration, focusing on the global spread of agriculture during the Neolithic period. He was also one of the founders in the creation of the Human Genome Diversity Project, or HGDP, an international scientific collaboration launched in the early 1990s to map the genetic diversity of human populations across the globe. Cavalli-Sforza’s interdisciplinary approach to studying human history and human evolution left its mark on the fields of both genetics and anthropology in the twentieth and twenty-first centuries.

In 2004, the Havasupai Tribe filed a lawsuit against the Arizona Board of Regents and several Arizona State University professors after discovering that the scientists had used blood samples from members of the tribe for research on type 2 diabetes in unrelated genetic studies. The study participants were not aware the researchers were using their samples in the study of highly taboo topics in Havasupai culture, such as schizophrenia, ethnic migration, and population inbreeding. The Havasupai Tribe alleged that the collection of samples constituted a violation of informed consent, or an individual’s agreement to participate after receiving an accurate and comprehensive explanation of the intended usage of their genetic material. The lawsuit, Havasupai Tribe v. Arizona State University Board of Regents, reached a settlement in April 2010 that included monetary compensation from Arizona State University and the return of the samples to the Havasupai community. Although the case did not set an official legal precedent, it sparked discourse regarding informed consent and ethical research practices when conducting genetic research with Native American communities and other vulnerable populations.

Joseph Grafton Gall researched and taught cell biology for over seventy years in the late twentieth and early twenty-first centuries in the United States. Much of his early work revolved around the structure and function of chromosomes, which are structures made of DNA and protein found in cells. As a professor at Yale University in New Haven, Connecticut, Gall and his graduate student Mary-Lou Pardue developed in situ hybridization, a technique that uses probes to identify the location of specific DNA sequences along a chromosome. With another graduate student, Elizabeth Blackburn, he also performed research on the structure of telomeres, which are the ends of chromosomes. Gall was an early advocate for women in STEM and trained many female scientists, many of whom became successful in their fields. Gall studied the structure and function of different forms of genetic information, namely DNA and RNA, helping to expand the understanding of how those molecules replicate within cells.

Polymerase chain reaction, or PCR, is a technique that scientists use to rapidly make millions of copies of deoxyribonucleic acid, or DNA, which is the genetic material found inside every living organism. Kary Mullis, who shared the 1993 Nobel Prize in Chemistry for his contributions to PCR, developed the idea for its underlying biochemical mechanism in the early 1980s while working at Cetus Corporation, a company in Emeryville, California, that used biology to create tools for medical treatments, including cancer. Over the next several years, Mullis and his Cetus colleagues developed the technology, publishing the first study to reference PCR in the journal Science in 1985. Cetus scientists further enhanced PCR by adding Taq polymerase, an enzyme that helps copy DNA and remains stable at high temperatures. Prior to the development of PCR, researchers used slow, difficult methods to study small amounts of DNA. PCR facilitated the rapid and affordable amplification of DNA, helping with tasks like diagnosing diseases, solving crimes, and testing food and water for bacterial contamination.