Leonard Lerman, Molecular Biologist, Dies at 87 Leonard Lerman, a molecular biologist whose discovery of how to manipulate DNA was a vital preliminary step in enabling others to decipher the basic building blocks of the genetic code, died on Sept. 19 at his home in Cambridge, Mass. He was 87. The cause was complications of a chronic neurological disease, his longtime partner, Lisa Steiner, said. In the late 1950s, while working at the University of Colorado School of Medicine, Dr. Lerman began testing his hypothesis that certain chemicals would attach to DNA by inserting themselves between molecules in the DNA strand. These intrusions would cause the DNA strands to unwind and sometimes lead to mutations. Although he did not publish his first paper on the topic until 1961, Dr. Lerman took these insights with him when he went to the Medical Research Council Laboratory of Molecular Biology in Cambridge, England, in 1959 for a sabbatical year to work with Sydney Brenner and Francis Crick. It was at this lab in 1953 that Dr. Crick and James Watson discovered the double helix structure of DNA, the building blocks of genetic material. By this time, Dr. Brenner and Dr. Crick were trying to determine how many nucleotides in strands of DNA encoded each amino acid, the building blocks of proteins. Dr. Lerman's experiments provided support for their hypothesis that they could mutate DNA by adding or deleting nucleotides. Their subsequent experiments enabled them to establish that groups of three nucleotides were the key to the code. In his essay "Masters of DNA," which gave a history of these discoveries, Sidney Altman, a student of Dr. Lerman's who went on to win the Nobel Prize in Chemistry in 1989, called his mentor's discovery "astounding." He said the finding amazed him "partly because one knew so little about how small molecules bound to DNA in a quite specific manner, and also because of the biological relevance of the discovery." But Dr. Lerman's research had significance far beyond the cracking of the triplet code. "His research shaped the way we manipulate and analyze DNA," said Barbara J. Meyer, a professor of genetics at the University of California, Berkeley. His approaches have facilitated the diagnosis of mutations associated with human genetic diseases. Leonard Solomon Lerman was born on June 27, 1925, in Pittsburgh to Meyer and Freamah Lerman. Both emigrated from the Pale of Settlement, a region of Imperial Russia where Jews were allowed to reside. Meyer Lerman was a buyer for a luxury department store, while Freamah Lerman tried to imbue her sons with a love of culture and learning. At 16, Dr. Lerman won a science radio show contest in Pittsburgh and was awarded a scholarship to attend the Carnegie Institute of Technology, now Carnegie Mellon University. He entered college before graduating from high school and proceeded to get his Bachelor of Science in five semesters. During World War II, he worked in an experimental weapons research lab. Then he went on to the California Institute of Technology to study under Linus Pauling, the Nobel laureate considered to be the father of molecular biology, and completed a Ph.D. in chemistry in 1950. Dr. Lerman's marriage, in 1952, to Claire Lindegren, ended in divorce in 1973. She later died. A second marriage, to Elizabeth Taylor, also ended in divorce. In addition to Ms. Steiner, his partner, he is survived by three children from his first marriage, Averil, Lisa and Alexander, and seven grandchildren. Ms. Steiner said of her partner that "better than being smart, he was creative," noting that he was always inventing gadgets. When his first wife complained that she did not like listening to commercials, Ms. Steiner said, he built a device that would turn the TV sound on or off remotely before such controls were commercially available. And after a visitor wearing a plaster cast on a broken leg once accidentally submerged it in water, she said, he jury-rigged a vacuum cleaner to dry the cast in a few minutes.