Recorded: 08 Jun 2004
The paper was written in 1987 and dealt with a way to isolate RNA from cells. The way I arrived to that method was because I was dealing with leukemia in children, childhood leukemia. And the samples were extremely scanty from these little babies. So I couldn’t use the current method. Then NCI together with Piotr Chomczynski we came up almost by chance on this method. In other words we found a way to isolate separately DNA from RNA. This was based on the ph of the solution we were using. And it came almost accidentally that I was using phenol that was buffered with the distilled water rather than a regular trace and we found these very wonderful RNA coming out from this small samples. Then we had the other colleagues at the NCI to try our method and they all had very good data. This spared us the agony to use the ultracentrifuge. I think this method was published by like the Single step method of RNA isolation in a journal that was not a prominent…it’s important, but was not the Nature or Science. It was Analytical Biochemistry. And over the years I understand at least fifty thousand people have used it and I think the fact that we could make it very simple to isolate from very, very few cells these molecules enabled techniques like PCR or micro array and so on and so forth. Then many, many companies capitalized on that, except myself. Because at the time I was too naïve and probably there was not yet the mentality to patent your own discovery. So only several years later I figured out that everybody was capitalizing on that technique and making millions of dollars out of it, but not me. Even here at this meeting everybody thought I became very rich out of it but it’s not the case. I never made any money out of it.
I’m glad that when I was here at Cold Spring Harbor here in '87, Dr. David Schlessinger at that time in St. Louis encouraged me to publish that method. One of the things I learned at Cold Spring Harbor was to have the courage to go out with your own innovative [innovation] and not compromise the idea. And at the time it was very instrumental his encouragement to publish that method. That was anti-conformist at the time. It was not following the stream. So that is when I learned from the Institute of Scientific Information in Philadelphia that that paper was so quoted. I was really stunned because I never followed over the years that one. Of course, it gives me a lot of satisfaction that many people used my system. It was born basically at the NIH when we were isolating these RNA from leukemic samples from babies.
RNA is the molecule that is transcribed from DNA. So it is another nucleic acid of extreme importance. And then to be able to isolate RNA enables you to study the expression of genes from the [understanding if genes not regulated] so expressed more, or less, both in [normal] and in cancer cells, and in disease. So that is probably the reason why the ability to analyze these molecules from just a very, very few cells be they yeast or drosophila or plant or cancer cell, probably made these technologies so diffuse to the standard I just explained before that everybody used. And on these technologies are hinged many, many other technologies that were developed later on like microarray for example, is still based on an RNA based technology. So all the RNA based technology benefited from that discovery, let’s put in this way. Again it basically was refracted DNA and RNA can be isolated by exploiting a different ph because they are two basically very similar molecules who are really difficult to disassociate one from the other one. We found that by using acidic ph you can actually sort them one from the other one and that was the basic research behind it.
Nicoletta Sacchi, Ph.D., is a Professor and Distinguished Member of the Department of Cancer Biology at the Roswell Park Cancer Institute in Buffalo, New York where she has been focusing on gene regulation in cancer cells since 2003. Native to Milan, Italy, she received her Ph.D. from the University of Milan in 1972, followed by postdoctoral work at Erasmus University, Rotterdam, at the Roche Institute of Immunology in Basel under Nobelist Georges Köhler.
In 1982 she came to the United States to continue her postdoctoral training at the National Cancer Institute. She returned to Italy in 1991 to become an Associate Professor at the University of Milan, until 1997 when she decided to make the US her home. That year she became a Visiting Scientist at Johns Hopkins University.
In 2002 Dr. Sacchi, was named the most cited women scientist and the 18th most cited scientist worldwide That year she received recognition for having the most quoted paper over the 20 year period from 1983 to 2002, "Single-step method of RNA isolation by acid guanidinium thiocyanate phenol chloroform extraction" Analytical Biochemistry 162(1):156-9,1987, which she co-wrote with Piotr Chomczynski.. This article has been cited over 56,000 times as of January, 2008.
Dr. Sacchi has been awarded the EMBO Award (1974 and 1981), the Soroptimist International Award (1976), AIRC Award (1984), the Gianina Gaslini Medal (1989), and the BIOTEC Award (1989.)