Elizabeth Helen Blackburn

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Elizabeth Helen Blackburn

American molecular biologist Dr. Elizabeth H. Blackburn (born 1948) is credited with the discovery of telomerase, an enzyme critical to the reproductive process of gene cells.

Dr. Elizabeth H. Blackburn is renowned for her discovery of the genetic enzyme "telomerase." Blackburn isolated and precisely described telomeres in 1978, thus enhancing the understanding of deoxyribonucleic acid (DNA) on the part of molecular biologists around the world. The subsequent discovery of telomerase in 1985 brought new insight into the complex functions of gene cells and the mysteries of their replication. Importantly, the discovery has given new hope to cancer researchers and opened new vistas for the science of gerontology.

Tasmanian Roots

Blackburn was born in Hobart, on the island of Tasmania (in Australia), on November 26, 1948. Her parents, Drs. Harold and Marcia (Jack) Blackburn, were physicians, and their only child quickly developed a love of science.

Higher Education

Blackburn started college at the University of Melbourne on the Australian mainland. There she completed her undergraduate studies, earning a bachelor of science degree in 1970. She continued at Melbourne and received her master of science degree in 1971. She went on to Cambridge University in England, where she earned a Ph.D. in molecular biology in 1975. She developed her doctoral thesis on sequencing of nuclear acids.

From England she moved to the United States, to Yale University in New Haven, Connecticut. At Yale, from 1975 until 1977, she studied chromosomes-their structures and replication-on a research fellowship. It was during those years that she first began to explore the phenomenon of telomeres, the tiny structures that cap the ends of chromosomes and which contribute to the stability of the gene cells.

In 1977 Blackburn moved to California, to the San Francisco Bay Area, to continue her research into the nature of the telomere projections of chromosomes. She worked, once again as a research fellow, at the University of California in San Francisco (UCSF). By that time she had traveled halfway around the world in pursuit of her educational goals. In 1978 she accepted her first position, as an assistant professor at the University of California in Berkeley.

The Discovery of Telomerase

As an assistant professor at Berkeley, Blackburn continued her research on the behavior of telomeres. Eventually she noticed a relationship between telomere size and the ability of a chromosome to divide and duplicate.

In 1985, she and her graduate assistant, Carol W. Greider, successfully isolated "telomerase." Telomerase is the enzyme that synthesizes new telomeres in DNA and controls the length of the telomeres. The discovery was a breakthrough for biologists everywhere. It enabled researchers to create artificial telomeres to control the duplication of gene cells. The discovery was a great stimulant to genetic research.

The historical discovery, isolation of the telomerase enzyme, brought international acclaim to Blackburn. In 1988, in recognition of her scientific accomplishment, she received the Eli Lilly Award for Microbiology. She was also elected a foreign associate of the National Academy of Science in 1993, having in 1990 received that academy's Molecular Biology Award. Yale University, home of her first postdoctoral research and her early studies of telomeres, bestowed her with an Honorary Doctor of Science degree in 1991. She was elected a Fellow of the Royal Society of London in 1992.

A Professor and a Writer

Blackburn was promoted to a full professorship at Berkeley in 1986, where she taught and managed a laboratory until 1990. She then transferred to the San Francisco campus of the University of California as a professor in the Department of Microbiology and Immunology and of Biochemistry and Biophysics.

In 1992, Blackburn was a contributing writer to the Harvey Lectures: 1990-91, an annual reference publication by prominent scientists. Harvey Lectures features information on biomedical research. The 1990-91 edition spotlights Elizabeth Blackburn, together with David Beach, and Francis S. Collins.

One year later, in 1993, Blackburn was named Chairwoman of the Department of Microbiology and Immunology at UCSF. That assignment further distinguished Blackburn: she was the first woman in the history of the university to hold the post.

In 1995 she published Telomeres (Monograph 29), a collection of essays on telomeres, which she edited along with Carol W. Greider. The book was well received, and, according to Science editor Carolyn Price, the publication, "is both timely and much needed. The literature [on telomeres] has become increasingly diverse and voluminous, making it difficult for the newcomer to the field…. Telomeres provides an excellent, easy-to-read introduction for such readers…. A major strength of the book lies in the breadth of its coverage and the way it links diverse topics…."

In 1990, with her students Guo-Liang Yu, John Bradley, and Laura Attardo, Blackburn published an article wherein they described the detrimental effect on genetic reproduction of the inability to make proper telomeric sequences. They found that telomeres cannot function properly when telomerase is defective. The telomeres eventually shrink, so that the genes cannot reproduce themselves properly, and the genes eventually die. This effect is significant to cancer research, because cancer cells are known to have excessive telomere length. Gerontologists (scientists who study the aging process) are also studying the effect of telomerase on telomeres, because the telomeres in human cells are known to shrink in connection with the aging process.

In addition to her research duties and her professorship at the University of California, Blackburn gives lectures and seminars on telomeres and cancer. She was among the presenters of the Dean's Research Seminar Series on Telomeres and Cancer in January of 1997. The Conference was transmitted via video relay to major San Francisco Hospitals.

Blackburn's scientific research is supported in part by the National Institute of General Medical Sciences (NIGMS). This work overall falls under the category of "basic biomedical research," or undirected research. This means that she is exploring to learn whatever can be known about cells. She is not looking for something in particular. The American Cancer Society also supports her work by providing postdoctoral fellowship assistance for her activities, and the National Science Foundation (NFS) supports predoctoral fellowship assistance for research by her students.

Personal Highlights

In all, Elizabeth Blackburn is a scientist, a teacher, a wife, and a mother. She met her husband, John Sedat, in England. Their mutual interest in molecular biology brought them together as students at Cambridge. They were married in 1975, after Blackburn moved to the United States. Sedat is a scientist in his own right, and is a professor of biochemistry and biophysics at UCSF. The couple has one son, Benjamin, born in 1986. Blackburn takes motherhood very seriously, and publicly attests to the importance of time spent with her family. In her on-line article, "Balancing Family and Career: One Way That Worked," she spoke out on several topics, including the importance of devoting the appropriate time to parenting.

In the article she upheld the right of every woman to choose a career without fear of discrimination for embracing motherhood. Blackburn commented, "It makes no sense that career avenues be closed to a woman because of a temporary situation [the responsibilities of mothering young children]…. [The woman who chooses to be a mother] has been educated and trained for years in her … work … a huge investment of her life…. [T]he culture … needs to change so that when a woman says she has family needs, she won't feel this forever damns her as a serious scientist."

Blackburn further discussed (in her article) the most memorable week of her life, which occurred at age 37 when she received her full professorship at UCSF and discovered in the same week that she was about to become a mother.

Professional Memberships

Blackburn was elected to the American Association for the Advancement of Science (AAAS) in 1991. She has been a foreign associate of the National Academy of Science since 1993, and a Fellow of the Royal Society of London since 1992. She served as president of the American Society for Cell Biology (ASCB) in 1998, and represented the ASCB to the Joint Steering Committee for Public Policy and Bioethical Research Advocacy.

Blackburn's discovery of telomerase brings new promise of the eradication of fungal infections such as those in "immunocompromized" patients, and hopes that new cures will be found for many cancers. Further research on telomerase one day might even provide a means to significantly slow the aging process that afflicts every human being.