Meselson, Stahl, and the Replication of DNA: A History of "The Most Beautiful Experiment in Biology" (2001), by Frederic Lawrence Holmes
In 2001, Yale University
Press published Frederic Lawrence Holmes'
book, Meselson, Stahl, and the Replication of DNA: A History of "The
Most Beautiful Experiment in Biology" (Replication of DNA)
chronicles the 1950s debate about how DNA replicates. That experiment
verified that DNA replicates semi-conservatively as originally proposed
by Watson and Crick. Rather than focusing solely on experiments and
findings, Holmes's book presents the investigative processes of
Franklin William Stahl (1929– )
Franklin William Stahl studied DNA replication, bacteriophages, and genetic recombination in the US during the mid-twentieth and early twenty-first centuries. With his colleague Matthew Meselson, Stahl performed an experiment called the Meselson-Stahl experiment, which provided evidence for a process called semi-conservative DNA replication. Semi-conservative replication is a process in which each strand of a parental DNA double helix serves as a template for newly replicated daughter strands, so that one parental strand is conserved in every daughter double helix.
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Irving Freiler Stein Sr. was a physician who studied women’s reproductive health during the twentieth century in the United States. In partnership with his colleague, Michael Leventhal, Stein identified a women’s reproductive disorder related to elevated male sex hormones, or androgens. The syndrome was originally called Stein-Leventhal syndrome and later known as polycystic ovarian syndrome. While studying the syndrome, Stein also helped establish a treatment for the condition, through the surgical removal of ovarian tissues. Stein identified the symptoms related to the condition polycystic ovarian syndrome, a hormonal imbalance estimated to be the most common female reproductive disorder as of 2017.
In a series of experiments in the late 1970s, Alec J. Jeffreys in the UK and Richard A. Flavell in the Netherlands developed a technique to detect variations in the DNA of different individuals. They compared fragments of DNA from individuals’ beta-globin genes, which produce a protein in hemoglobin. Previously, to identify biological material, scientists focused on proteins rather than on genes. But evidence about proteins enabled scientists only to exclude, but not to identify, individuals as the sources of the biological samples. By 1979, Jeffrey’s experiments on beta-globin genes shifted the analytical approach of scientific identification from proteins to genes to identify an individual’s genetic identity. The ability to match a person to a biological sample developed in the 1980s and impacted many fields including paternity testing, forensics, immigration, and body identification.
Martin Couney and Incubator Exhibits from 1896 to 1943
During the late 1800s and early 1900s, physician Martin Couney held incubator exhibits to
demonstrate the efficacy of infant incubators throughout the US and Europe. At his exhibits, Couney
demonstrated that isolating premature infants in an incubator ward could significantly decrease
premature infant mortality and increased the use of incubators in the US.
Etienne Stephane Tarnier (1828–1897)
Etienne Stephane Tarnier was a physician who worked with premature infants in France during the
nineteenth century. He worked at the Maternité Port-Royal in Paris, France, a hospital for
poor pregnant women. Tarnier developed and introduced prototypes of infant incubators to the
Maternité in 1881. Tarnier's incubators became standard in neonatal care, especially for premature
infants, enabling doctors to save many such infants that previously would have died.
Human Papillomavirus (HPV) Strains 16 and 18
Better Babies Contests in the United States (1908–1916)
Better babies contests were competitions held in state fairs
throughout the US during the early twentieth century in which babies
between the ages of 6 and 48 months were judged for their health. In
1908, social activist Mary de Garmo established and held the first
better babies contest at the Louisiana State Fair in Shreveport,
Louisiana. The contests, mirroring theories established in the US's
of the twentieth century, aimed to establish
standards for judging infant health. Nurses and physicians judged
infants participating in the contest on mental health, physical
health, and physical appearance. In 1913, the Woman's Home Companion
) magazine cosponsored de Garmo's better babies contests and
Harvey Leroy Karman (1924–2008)
Harvey Karman was an abortionist, inventor, and activist for safe abortion
techniques in the US during the twentieth century. Karman developed the Karman cannula, a flexible soft tube used for vacuum aspiration abortions. Karman traveled extensively throughout the US to educate healthcare providers on how to administer safe abortions. He also traveled to Bangladesh, India, China, and other developing nations to promote safe and simple abortion
techniques that anyone could perform without previous medical training. As of 2017, Karman’s abortion
technique and cannula continue to be widely used throughout the world for terminating early pregnancies.
Intrauterine Pressure Catheter
An intrauterine pressure catheter (IUPC) is a device placed inside a pregnant woman’s uterus
to monitor uterine contractions during labor. During labor, a woman’s uterus
contracts to dilate, or open, the cervix
and push the fetus
into the birth canal. The catheter measures the pressure within the amniotic space during contractions and allows physicians to evaluate the strength, frequency, and duration of contractions.