Sponsored by the U.S. Department of Energy Human Genome Program
Human Genome News Archive Edition
Human Genome News, January 1994; 5(5)
Laureates' Work Has Great Impact on Human Genome Project Research
Phillip Sharp (Massachusetts Institute of Technology) and Richard Roberts (formerly Cold Spring Harbor Laboratory, now New England Biolabs) were jointly awarded the 1993 Nobel Prize in Medicine and Physiology for their 1977 work on gene splicing. Sharp served on the Program Advisory Committee of the NIH National Center for Human Genome Research from 1988 to 1991.
Working independently, Sharp and Roberts discovered that genes in eukaryotic cells are distributed among widely spaced segments separated by introns (DNA segments that have no apparent protein message); about 99% of human genes are believed to share this structure. In a dramatic change from commonly accepted theories, human genes were thus shown to differ markedly from often-studied bacterial genes, which run continuously along the DNA strand. Research indicates that some introns have persisted for a billion years, and even though they do not carry translatable code, they may provide an evolutionary advantage. Interruptions in the code may facilitate the creation of new combinations and allow species to evolve.
The investigators also showed that after DNA is copied into a primary RNA transcript, introns are deleted and the remaining genetic material is spliced together in the correct order. The edited message then leaves the cell nucleus and travels to the ribosomes, where it is translated for protein assembly. Mistakes in RNA processing are related to a number of disorders including thalassemia, and recent results suggest these editing mishaps may also play a role in cancer.
The Nobel chemistry prize was awarded to two investigators for techniques that have become standard in research and clinical laboratories throughout the world. Kary B. Mullis, who is now an independent consultant in molecular biology, was employed by Cetus, Inc., in 1984, when he conceived the polymerase chain reaction (PCR). PCR allows investigators to make millions of copies of any specific region of a DNA sample in a very short time. Because the reaction can amplify minute amounts of sample, PCR has had an especially profound impact in clinical medicine, genetic disease diagnostics, forensic science, and evolutionary biology. PCR has become an essential tool for genome researchers, who use it to detect the presence of unique landmarks (e.g., sequence tagged sites) in a much larger DNA sample (such as pools of clones) and amplifying them for use as probes or starting material for sequencing.
Mullis shared the chemistry prize with Michael Smith (University of British Columbia, Vancouver) who formulated a method that enables scientists to induce specific mutations in normal genes and then examine their altered protein products. This site-directed mutagenesis technique is used by researchers involved in molecular biology and protein engineering to investigate gene function and create new and potentially useful proteins for medicine and industry. As the goals of the Human Genome Project are realized and the estimated 100,000 genes in the human genome are identified, gene-hunting activities will increasingly give way to studies focusing on how genes work to guide development and function of all organisms.
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Human Genome Program, U.S. Department of Energy, Human Genome News (v5n5).
The Human Genome Project (HGP) was an international 13-year effort, 1990 to 2003. Primary goals were to discover the complete set of human genes and make them accessible for further biological study, and determine the complete sequence of DNA bases in the human genome. See Timeline for more HGP history.
Published from 1989 until 2002, this newsletter facilitated HGP communication, helped prevent duplication of research effort, and informed persons interested in genome research.