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Nobel Prize summary
In the 1970s, Michael Smith developed a general method for producing mutations in a gene, not in a random fashion but at specific positions determined in advance from the sequence of the nucleotides in the gene. This method of site-directed mutagenesis has created completely new opportunities to study the properties of protein molecules: how they function as catalysts or as signal transmitters through membranes, which factors determine how they fold into specific three-dimensional structures and how they interact with other molecules in the cell. Such protein engineering is also of importance in modern biotechnology and drug design. Novel antibodies have been created that can kill certain cancer cells. Plants that produce proteins enriched in essential amino acids are being field tested and in the future this method might produce engineered wheat and corn flour that has the same nutritional value as meat.
Isolation and amplification of a specific gene was one of the outstanding problems in DNA technology, including site-directed mutagenesis, until 1985 when Kary Mullis presented the Polymerase Chain Reaction, now commonly known as PCR. Using this method it is possible to amplify and isolate in a test tube a specific DNA segment within a background of a complex gene pool. In this repetitive process the number of copies of the specific DNA segment doubles during each cycle. In a few hours it is possible to achieve more than 20 cycles, which produces over a million copies.
The PCR method has already had a profound influence on basic research in biology. Cloning and sequencing of genes as well as site-directed mutagenesis have been facilitated and made more efficient. Genetic and evolutionary relationships are easily studied by the PCR method even from ancient fossils containing only fragments of DNA. Biotechnology applications of PCR are numerous. In addition to being an indispensable research tool in drug design, the PCR method is now used in diagnosis of viral and bacterial infections including HIV. The method is so sensitive that it is used in forensic medicine to analyze the DNA content of a drop of blood or a strand of hair.
Isolation and amplification of a specific gene was one of the outstanding problems in DNA technology, including site-directed mutagenesis, until 1985 when Kary Mullis presented the Polymerase Chain Reaction, now commonly known as PCR. Using this method it is possible to amplify and isolate in a test tube a specific DNA segment within a background of a complex gene pool. In this repetitive process the number of copies of the specific DNA segment doubles during each cycle. In a few hours it is possible to achieve more than 20 cycles, which produces over a million copies.
The PCR method has already had a profound influence on basic research in biology. Cloning and sequencing of genes as well as site-directed mutagenesis have been facilitated and made more efficient. Genetic and evolutionary relationships are easily studied by the PCR method even from ancient fossils containing only fragments of DNA. Biotechnology applications of PCR are numerous. In addition to being an indispensable research tool in drug design, the PCR method is now used in diagnosis of viral and bacterial infections including HIV. The method is so sensitive that it is used in forensic medicine to analyze the DNA content of a drop of blood or a strand of hair.
Submitted on December 6, 2003 in By David.
