Dr. John Cairns, a prominent molecular biologist and a pioneer in cancer research, has arrived in the United States to take up his appointment as professor of Microbiology at the School of Public Health (SPH).

Cairns, who in 1960 made significant discoveries about the replication of DNA, was formerly the director of the Mill Hill Laboratories of the Imperial Cancer Research Fund in Great Britain. He plans to continue his research of the effects of mutagenic elements (DNA-damaging substances) on common bacterial cells. His work may have implications for understanding how cells protect themselves from carcinogens in the environment.

Cairns was appointed to the microbiology chair last summer but did not arrive here until this semester.

Jay A. Winsten, Policy Director for the SPH, last week called Cairns' efforts to replicate DNA a "major breakthrough in cancer research. He cited Cairns as "one of the world's most highly regarded cancer specialists as well as a leading microbiologist."

"A lot of people at the School, of Public Health certainly welcome his coming here," Winsten said, adding that Cairns will probably teach a seminar in the Fall.

David Dressler, lecturer in Biochemistry and Molecular Biology, said Cairns had done "elegant work" and that his appointment would "strengthen the intellectual foundation of the school of Harvard."

Cairns, who in 1960 made significant discoveries about the replication of DNA, will be leaving his position as director of the Mill Hill Laboratories of the Imperial Cancer Research Fund in Great Britain. Cairns said Friday that he accepted the Harvard appointment because it would allow him to teach as well as continue his research in cancer causes.

Before directing the Mill Hill Laboratories, Cairns was professor of Microbiology at Stonybrook College in Long Island.

Speaking at the SPH last Wednesday, Cairns questioned current methods of studying causes of cancer. He said that he was not convinced that localized mutations were responsible for the majority of cancer cases, as is now believed.

"Mutations are certainly a major cause of cancer," Cairns said, "but I think that the transportation of DNA from one chromosome to another is also a major cause of cancer. Many researchers look only at mutants or at industrial causes like smoke inhalation and overlook the role of DNA transportation."

Cairns said Friday that although he believed that the vast amount of money spent each year on cancer research is justified, scientists are far from discovering a cure for the disease.

"There is still a lot more that scientists have to learn about DNA before any breakthroughs are made," Cairns said, adding that "much confusion still surrounds cancer research."

Howard H. Hiatt, dean of the SPH, yesterday called Cairns' appointment particularly significant because "few people with his background in molecular biology have applied that background to human problems.