The Iowa Stater
May 2001
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DNA, RNA, GMO—huh?
"You say gen-oh-mics, I say gen-ah-mics..."On occasion, we say "forget it" when trying to decipher the code words that define the all-encompassing world of biotechnology. The discipline's implications are phenomenal for our universe, and Iowa State has emerged as a leader in biotechnology research. But beyond vague memories of eighth-grade biology tests and filling in every third blank with "DNA," many of us have moved far beyond our comfort zones in grasping the fundamentals of this field of study. Relax. The following "primer" offers real-world definitions to the terms most commonly used in the popular press to define biotechnology. Read on, and before you know it, you'll be wranglin' data with the best of 'em.
Cells 101: OK, let's start with the basics. First, you gotta have a cell. And in that cell's nucleus, or center, you'll find stuff that's both microscopic and mighty.
Like DNA. Three simple letters that signify a) deoxyribonucleic acid and b) the blueprint of all life. Twist two strands of hair together: That's how DNA looks, all one one-millionth of an inch of it.
Remember these four letters when describing the composition of DNA: A, T, C and G. The specific order and number of these four letters determines the characteristics of every living organism, like letters determine words in our alphabet. Some random combinations, though, signify nothing, and are known as junk DNA. Get this: Every cell in the human body contains 3 billion letters.
DNA contains the instructions for creating proteins. Proteins actually are the workers in the cells. They determine whether we're tall or short, or whether a plant leaf will be solid-colored or speckled. Hemoglobin, for instance, is a protein that your red blood cells need to carry oxygen throughout your body.
Ribonucleic acid, or RNA, is a molecule similar to DNA, but smaller and more mobile. RNA makes sure that messages encoded in DNA are converted into proteins.
Microscopic "clumps" of DNA are called chromosomes. Each human cell contains 23 chromosome pairs, sets donated jointly by your mother and father.
The gene goes through life on the back of a chromosome. The gene is really "the boss" of the cell, calling the shots for both its structure and its metabolic function.
All the genes, or DNA, or total hereditary material in a cell, is called a genome. You also can think of the genome as the instructions for making an organism. Genomics is the study of all the genes in an organism and the set of tools that scientists use to study and understand all the genes in an organism.
Now that your own gray matter has kicked into gear, here's where "biotech" fits in.
Simply put, biotechnology uses the latest tools and techniques to improve life by understanding and restructuring genes. As one ISU scientist put it, "Using yeast to make bread 5,000 years ago was biotechnology. Today, we're just using different tools."
For example, "molecular scissors" cut DNA strands at specific spots, allowing scientists to harvest only one or more particular genes from a cell. Other tools help insert a gene into a new cell's DNA. Perhaps holes are punctured into the new cell's membrane, or maybe the new cell is floated in a solution that creates holes for penetration. Electric currents also can serve as tools to create spaces into which the gene can float.
Genetic engineering: Also known as gene splicing, gene transformation or bioengineering. Genetic engineering uses recombinant DNA technology to insert a new gene into an organism, usually from another organism. This process results in a new function, like insect resistance, herbicide tolerance or a new flower color. Insulin, a medication used in the treatment of diabetes, is the result of recombinant DNA. The human insulin gene is inserted into an E. coli bacterial cell. The cell divides into new cells that produce the insulin.
Riboenzymes are RNA pieces that act as enzymes. Enzymes are what get things started, like the way your morning cup of coffee gets you going. Riboenzymes may possibly eliminate defects in genes that cause diseases like sickle cell anemia.
When a gene is functioning,it is "expressing" or telling a specific cell what to be. Scientists call this gene expression. For example, the genes used to make a corn tassel are different than those needed to produce an ear of corn. Different genes are expressed in different parts of the plant, and at different life stages.
These next two processes — which sound similar but serve different functions — are all about organization. Gene mapping is determining the positions, or locations, of genes on chromosomes. Genome sequencing is determining the linear order of the As, Ts, Gs and Cs on a chromosome's DNA strand.
Cloning is the process of creating cells that are identical in nature. These cells possess all the same chromosomes, physical attributes and functions. Cancer cells are considered natural clones, reproducing themselves rapidly. Cloning was a hot topic a few years ago when "Dolly," the first cloned mammal (a sheep) made international headlines. And there currently are groups attempting human cloning projects.
GMO has become almost as common as "SUV" or "ASAP." This acronym stands for "genetically modified organism." It's the resulting product of a genetic engineering experiment and also is known as transgenic, or a biotechnology enhanced product. The Bt corn plant, for instance, is a well-known GMO. The gene Bt produces a toxin used in corn pesticides. When that gene is inserted into a corn plant, the plant produces its own anti-pest toxins. This particular project has stirred debate among scientists and environmentalists over the safety of these products and their impact on the environment.
Bioethics is trying to decide whether being able to do something means we should do it. Bioethicists routinely pose questions regarding genetic orchestration, like, "Should parents be allowed to conceive a child for the purpose of harvesting its cells to aid another ailing family member?" or, "Are there health risks in consuming genetically modified foods?" Iowa State includes a bioethetics program in its curriculum.
Another process for which Iowa State has made room in its curriculum is bioinformatics, or using computers to study biology and biotechnology. Also known as "data wrangling," bioinformatics involves organizing, storing, cross-referencing and accessing vast amounts of data, genetic codes, 3D images and statistics. Last year, the university launched a doctoral program in bioinformatics and computational biology to respond to the escalating need for specialists in this discipline.
— Debra Gibson
University Relations