The case for serendipity

Gary Kuhlmann
Published: January, 2009

Progress in biomedical science owes much to serendipity. Basic research, or the simple curiosity about how things work, has led to many of the discoveries that have transformed health, medicine, and our understanding of human disease. Here is Lens magazine’s list of the “top 10” discoveries in biomedical science in the 20th century.

Genetics, 1910.

Experimenting with the common fruit fly, Drosophila melanogaster, Columbia University embryologist Thomas Hunt Morgan demonstrates that genes are the mechanical basis of heredity, thereby launching the modern science of genetics.

Morgan reportedly tells colleagues about experiments that lead to unexpected results: “They (the flies) will fool you every time.” His first attempts to find tractable mutations fail, but Morgan perseveres and discovers the white-eyed fly, which leads to his discovery of sex-linked inheritance.

Cholesterol, 1913.

A Russian finding -- that cholesterol is the main dietary culprit in atherosclerosis -- languishes for decades until researchers at the University of California, Berkeley, establish in a landmark 1950 paper the role of lipoproteins in the disease.

In the early 1970s, Michael Brown and Joseph Goldstein at the University of Texas Southwestern Medical School in Dallas discover cholesterol receptors and the mechanism by which blood cholesterol is regulated. After a National Institutes of Health study establishes that lowering cholesterol lowers the risk of heart attack, the stage is set for the introduction of the first cholesterol-lowering statin drugs in 1987.

Insulin, 1921.  

When Canadian surgeon Frederick Banting gives up his struggling practice, he goes into the research laboratory to follow a nagging hunch about a cure for diabetes. In 1921, he and his assistant Charles Best reverse diabetes in a dog by injecting a concoction of pancreatic extracts.

John J.R. McLeod and James Collip at the University of Toronto help them purify the extract, and in 1922, insulin saves the life of 14-year-old Leonard Thompson. Within a year, the manufactured protein becomes available worldwide.

Penicillium mold in a Petri dish.

Image provided by Visuals Unlimited.

Penicillin, 1928.

Scottish bacteriologist Alexander Fleming accidentally grows a culture of penicillin in a dirty Petri dish. At the outbreak of World War II, scientists at Oxford University, working with scant wartime resources, show penicillin can clear a range of infections without the toxic effects of sulfa drugs.