Biotechnology and the manipulation of genes.
Biotechnology has progressed to creating things that do not exist in nature from manipulations of genes and other proteins in a manner much like what has occurred naturally during evolution. An example is one of the most profuse tools in biotechnology, using enzymes to splice pieces of DNA at particular locations. These are the basis for what has been made possible through the understanding and manipulation of molecular evolution during the second half of the twentieth century. Remarkably, additional studies revealed that the very enzymes used in the lab to splice DNA for the scientists’ own purposes are actually evolved in bacteria to protect them from attacks by viruses. The result is that splicing enzymes—enzymes that cut DNA in particular places—are formidable weapons that natural selection evolved to protect the bacteria from viruses. The enzyme splicing is effective because those enzymes can recognize the viral host DNA as distinct from bacterial DNA. Molecular biologists have, through evolution research, discovered a valuable class of enzymes which are useful in medicine and agriculture.
David Erickson, PhD., teaches microbiology at BYU and researches the transmission of bubonic plague by fleas. He studies the infection process and is interested in genes that help the plague germs make their way from the mammal to the flea and back again. His studies are basic evolution, and his findings shed light on a fascinating co-evolutionary parasitosis that involves bacteria, fleas, and humans. He and his students found that once inside the flea, the plague bacteria produce a sticky polysaccharide glue the conglomerates to plug the flea’s esophagus causing the flea to starve. When the cold-blooded flea feeds on a warm-blooded human, plague bacteria are first injected in clumps held together by the glue, but once in the human, the glue is promptly dissolved and spreads rapidly. Dr. Erickson is working on a vaccine that attacks the glue form, so that as soon as the body encounters
A slight mutation in the matched nucleotides can lead to chromosomal aberrations and unintentional genetic rearrangement. (Photo credit: Wikipedia)
it, and before the glue has a chance to melt, the bacteria are attacked. He proposes to use a vaccine against the flea version rather than the human version of the plague. Additional work coming from Erickson’s lab based on the basic research has produced transgenic mosquitoes that are incapable of transmitting diseases which opens new avenues for attacking vector borne infections diseases of humans.
BYU professor, Jim Porter, PhD.’s research involves the fetal origins of adult disease at a basic genetic level. He and his students are evaluating an hypothesis that environment during pregnancy repro-grams the genes of the fetus which impact the individual throughout life. He studies pregnant rats and focuses on cardiovascular health. Porter and his students have found that female rats that were gestated on high salt and later stressed, had significantly higher blood pressure and heart rate compared to control rats on a normal diet. Out of about 30,000 genes in the rat, the investigators have narrowed their work down to just one gene that appears to be involved. It is of interest that the same gene is also found in humans, another example of evo-devo. Dr. Porter states, “it appears that the mother is not passing on salt itself to her babies, but rather she’s passing on some sort of genetic signal which affects her pups later in life. The response seems to be originating in the brain”.
- Agriculture. In 1798, Thomas Malthus published An Essay on the Principle of Population, surmising that population growth would always out run food production. At that time, about 5 acres of land were required to produce food for each one of the Earth’s one billion people. In 2009, there were more than 6 billion—and in 2014, nearly 7 billion–and each of them eats from about ½ acre. How did this tenfold increase in production happen? Among the many steps taken to keep food available, one of the most important was the introduction of hybrid vigor in plant breeding as a direct result of practical application of Darwin’s principles of selection for evolution. The biggest single leap forward, however, was the so-called Green Revolution of the 1940s-1960s wherein genes were bred into cereal crops by laboriously crossbreeding thousands of plant varieties from around the world. This application of basic molecular biology–the genetic forces of evolution–made it possible to save over one billion people from starvation.
Another agricultural revolution has begun that is dwarfing those that preceded it. A by-product of evo-devo makes it possible to map and understand genes on a molecular level. Now agricultural scientists can give specific desired characteristics to plants, animals, and microorganism. This scientifically grounded set of processes makes it pos-sible to avoid long hit-and-miss, trial-and-error efforts. We can now select specific genes and insert them where they are needed, use more than one copy of a gene, and can turn genes on and off to suit our needs to protect against diseases, insects, and drought. The new gene altered products have improved nutritional food content, can live in colder and hotter climates, and have a longer seed and product. This is self-preservation, and it is a direct outgrowth of evolution.
Norman Borlaun, aptly called the father of the Green Revolution, commented in the Wall Street Journal on the Gene Revolution. Among the things he said were:
“Since 1906, the planting of genetically modified crops developed through biotechnology has spread to about 250 million acres around the world…In each of the last six years, biotech cotton saved U.S. farmers from using 93 million gallons of water in water scarce areas, 2.4 million gallons of fuel, and 41,000 person-days to apply the pesticides…Agricultural science and technology, including the indispensable tools of biotechnology, will be critical to meeting the growing demands for food, feed, fiber, and biofuels…This flourishing new branch of science extends to food crops, fuels, fibers, livestock, and even forest products.”
And it is based on the solid principles of Darwinian evolutionary theory related to heritable changes associated with natural selective processes.
In 2007, U.S. farmers were engaged in the Gene Revolution by using genetically modified seeds for 75% of the corn, 87% of the cotton, and 91% of the soybeans planted. Milk is coagulated to make cheese by an enzyme originally extracted from the stomachs of young calves, but now raised in yeast cells containing calf genes. The Gene Revolution is spreading world-wide. The anticipated world population in 2050 will be about 9 billion people who will need to be fed. Present day technology and new innovations from gene research will be necessary to continue to prove Malthus wrong and to ensure survival and good nutrition for all the Earth’s population. Today’s basic genetic research is being translated into genetic technology at an astounding rate; current genetic technology is processing that genetic information thousands of times faster than approaches used just a generation ago, and with unprecedented accuracy. From today’s perspective, with what has been learned from the study of evolution, the future seems to be assured.
The Life Sciences and Department of Biology at Brigham Young University (BYU) is very active in studying and pursuing basic evolutionary/genetic/cellular biology research in a wide assortment of fields. Rex Cates, PhD., researches medicinal plants used by rural people in Morocco, Guatemala, Ecuador, and the U.S. desert southwest. He and his students focus on plant extracts that have reduced toxicity to normal human cells, but that are active against diseases such as herpes virus, E-coli, various cancers, Staphylococcus, and yeast infections. Of 200 plants and lichens tested, 20% have yielded promising extracts, and four are extremely promising, according to Cates. His work has shown that many of the plants studied have important activity against human diseases and low toxicity to normal cells.
Joel Griffitts, PhD., teaches bacterial genetics at BYU and investigates interactions between bacteria and plants. Dr. Griffitts points out that the “whole living world would not be what it is without [the unique interaction between special bacteria and legumes].” Further, as one example, he has researched a soil-borne bacteria, rhizobia, that infects the roots of alfalfa. In a fascinating evolutionarily selected symbiotic relationship, the infected plant creates a fleshy root nodule around the bacteria. Dr. Griffitts observed that, once within the alfalfa, “they transform themselves and take on the capacity to convert nitrogen from the air into fertilizers.” The bacteria and the alfalfa have established a very close and cooperative relationship. What triggers new genes to be expressed and a differentiation event to occur once the bacteria encounters the plant is Dr. Griffitts’ and his students’ focus of study. This is as much the study of evolution as Sean B. Carroll, PhD.’s commitment to finding out how evolution takes place with his involvement in basic evolutionary development. Dr. Griffitts says, “my vision is that we will be able to identify the full suite of plant and bacterial functions that allow a symbiotic interaction to occur. Perhaps one day we will be able to transfer what we know about this system to cereal crops that don’t naturally engage these bacteria the way legumes do.”
Dr. Josh Udall is a professor of genetics and genomics at BYU who works to improve salt and drought tolerance in cotton. He focuses on his knowledge that cotton is a diploid; it carries two copies of all genes. His work is an attempt to activate both copies of the genes involved in drought tolerance or to silence a gene copy that is making cotton susceptible to stress. Udall and his students work at the molecular level measuring the expression of thousands of genes at a time in order to identify those genes associated with salt stress. Dr. Mark J. Rowe of the Department of Nutrition, Dietetics, and Food Science at BYU recently retired. His work involved the use of mitochondrial genetics to research obesity and longevity.
Andre Chanderbali, PhD., is the lead author of a study on ancient flowers at the University of Florida’s Museum of Natural History. The starting place for their study is that “the origin of the flower is the key to the origin of angiosperms (flowering plants)”. The goal of their research is to understand the original regulatory program (something on the order of the Hox genes in animals), or set of genetic switches, that produced the first flower in the common ancestor of all living flowering plants. Better understanding of these genetic switches holds an eventual goal of helping scientists in fields such as medicine or agriculture, including help in growing plants used to fight disease or developing more drought-resistant crops.