By Robert C. Cowen, writer of The Christian Science Monitor
The Christian Science Monitor
THERE'S a new "biotech" revolution under way that promises a big payoff for farmers.
It uses modern methods of molecular biology borrowed from the worldwide effort to chart the human genetic blueprint to map out the simpler genetic blueprints of plants and animals. With these methods, breeders can dramatically speed up improvement of crops and livestock without having to use controversial and highly regulated "genetic engineering" techniques. That's the message a panel of agricultural scientists brought to the recent annual meeting of the American Association for the Advancement of Science (AAAS).
Plant breeder Mark Sorrells of Cornell University at Ithaca, N.Y., told a press conference that "recent advances in biotechnology are having a fairly dramatic impact on plant breeding." He added: "Many of these changes ... are paralleling ... human genome research projects. They use the same techniques and often are applied in precisely the same way."
This is an important early spinoff from the effort to map the human genome - the set of genetic instructions that govern human biological development from conception to birth - in which the United States alone expects to invest several billion dollars over the next 10 to 20 years.
Genome instructions for people, plants, and animals are encoded in the chemical structure of long molecules of a compound called deoxyribonucleic acid or DNA. Coherent segments of DNA that control different aspects of biological development are called genes. The DNA molecules carrying the genes are grouped together in bodies called chromosomes. These chromosomes carry the genetic heritage that parent organisms pass to their offspring generation after generation. Precise mapping
What the genome explorers are trying to do is map the precise location of various genes on the chromosomes. They want to tag the genes with distinctive markers the way a "dig safe" crew tags underground cables with distinctive little flags.
The tags are DNA sections that do not themselves take part in gene action. They may be small repetitive sequences called microsatellites or other structures that biochemical probes can recognize.
Gene-tagging technology is developing fast to meet the needs of human genome mapping. That is a long-term project. The practical payoff today lies in the fact that the technology already is at a stage where rapid progress is being made in mapping crop plant and livestock genomes. This is what is beginning to revolutionize plant and animal breeding. …