Maclyn McCarty

Maclyn McCarty (June 9, 1911 – January 2, 2005) was an American geneticist. He was the last surviving member of a scientific team in Manhattan that made a big discovery in the 1940s. This team showed for the first time that genes were made of DNA, not protein, which was what people used to believe.

McCarty worked at Rockefeller University for more than 60 years. His most famous work was part of what is called the Avery–MacLeod–McCarty experiment. In this experiment, he and his team studied bacteria called pneumococcus. They found out that the substance that carried genetic information in these bacteria was DNA. This discovery helped scientists understand how traits are passed from parents to children, not just through biology but also through chemistry.

In 1994, the world celebrated the 50th anniversary of this important discovery. McCarty’s work changed the way we study life and heredity. He devoted his career to studying diseases caused by tiny organisms and passed away from congestive heart failure.

Early life

Maclyn McCarty was born in South Bend, Indiana. He was one of four brothers. His father worked for the Studebaker Corporation.

He studied biochemistry at Stanford University, where he worked with James Murray Luck. He graduated in 1933 and later earned his medical degree at Johns Hopkins University in 1937. After additional years at New York University, he joined Rockefeller University, where he met his future research teammates.

Early Rockefeller years

When Maclyn McCarty joined Rockefeller University, he worked with a team that had already made important progress. Over the next few years, they continued their research. In 1944, they published their findings in the Journal of Experimental Medicine, showing a strong link between DNA and biological activity.

At first, many scientists were unsure about the idea that genes were made of DNA. It took time for others to accept this discovery. It wasn't until 1953, after Watson and Crick's bihelical structure of DNA was revealed, that most researchers agreed with their work from 1944.

Later career years

After retiring in 1946, McCarty took charge of a specialized laboratory where he worked alongside scientist Rebecca Lancefield. Together, they discovered that infections could lead to conditions affecting the joints and heart weeks later. McCarty studied these infections by examining patients and their biological samples.

McCarty and his team made significant advances in understanding bacteria, particularly a type called group A streptococci. They studied the structure of these bacteria and identified important components like polysaccharide and peptidoglycan. They also developed tests to detect immune responses to these bacteria, which helped in diagnosing diseases such as rheumatic fever. McCarty’s work improved medical practices, including the use of C-reactive protein levels to detect inflammation.

In his later years, McCarty became a leader in biomedical science. He held important positions at Rockefeller University and advised many organizations, including the Helen Hay Whitney Foundation, the Institute of Medicine, and the Journal of Experimental Medicine. He was also a member of prestigious groups such as the United States National Academy of Sciences, the American Academy of Arts and Sciences, and the American Philosophical Society.

Personal life

Maclyn McCarty had a rich personal life filled with close friends around the world. He was known for his warmth, wit, and love for English literature, theater, and symphonies. He enjoyed exploring cities like Paris, New York, and London, especially after retiring. McCarty also stayed close to his family, with his four brothers meeting yearly for reunions.