Dr. Leonard D. Hamilton, of Crane Neck in Old Field, a medical researcher who played a key role in the discovery of the structure of DNA, died June 29 at the age of 98.
In the late 1940s and early ’50s, he developed techniques for extracting and purifying mammalian DNA, which he supplied to Maurice Wilkins and his associates to enable them to generate X-ray crystallography images from which the double helical structure of DNA was inferred — the discovery for which Maurice Wilkins, James Watson and Francis Crick shared the Nobel Prize in Physiology or Medicine 1962.
Born in Manchester, England, Hamilton received medical degrees from Balliol College, Oxford University, and a doctorate in biochemistry from Trinity College, Cambridge. He married Oxford student Ann Twynam Blake in 1945. They came to The University of Utah in Salt Lake City in 1949 on a one-year grant and decided to stay. He worked at what is now Memorial Sloan Kettering Cancer Center in New York City from 1950-64, primarily on DNA in collaboration with Wilkins at Kings College, London, and on cancer research and treatment. He also worked for the U.N. Scientific Committee on the Effects of Atomic Radiation, contributing to its seminal report on that subject in 1962. He continued his biomedical research as head of the Division of Microbiology, Brookhaven National Laboratory, and became a professor of medicine at Stony Brook University in 1968. From 1973 until his 1994 retirement, he led a team at Brookhaven analyzing the health effects of different energy sources.
Hamilton’s wife Ann — a New Democratic Coalition and pro-choice activist, who worked as a psychiatric social worker at the Sunrise clinic in Amityville — died in 1997. He is survived by daughter Jane Dorwart; two sons, Stephen Hamilton and Dr. Robin Hamilton; seven grandchildren; and sister Elaine Wolfe of Great Neck.
Donations to The Nature Conservancy in his name would be appreciated by the family.