Cloning may make possible some extraordinary advances in the science of genetic engineering. It may speed up mammalian research, and make possible the introduction of desired traits into higher mammals. There are many different levels at which genetic engineering may occur, some of which have been going on for a long time. Read my summary of one way in which cloning may make possible new advances in genetic engineering. This page provided courtesy of:

The BioFact Report

Frequently Asked Questions

Types of Genetic Engineering

Natural Selection

Natural Selection is nature's own form of genetic engineering. The most fit organisms survive through natural selection. The rate of evolution of new species through natural selection is incredibly slow, but methods have been discovered by which nature has optimized the process.

The entire genome (all the genes) of higher animals and plants are broken up into functional components known as exons and separated by regions called introns. Special genes known as transposable elements serve to mix and match functional components of genes in an effort to maximize the likelyhood of creating better genes and organisms. There is some evidence that bacteria, one of the simplest organisms, had introns and exons in some past era, but lost them in favor of efficiency and other means of acquiring new DNA.

Selective Breeding

Selective Breeding or "Unnatural Selection", is man's most basic effort at genetic engineering by creating our own selective pressures. Many conventional farm animals, domesticated dogs and cats were likely created ages ago by selectively breeding animals together with desired traits. Gregor Mendel helped to establish the rules of genetics through his work selectively breeding plants in the 1800's. Selective Breeding has worked well for engineering animals and plants, but it can take whole human lifetimes to bring about small changes in a species.

Through unnatural selection certain attributes and characteristics can be enhanced by selectively killing all organisms that do not have the desired traits. This has been suggested by some as a viable option for genetically engineering humans. Parents could produce a large number of fertilized eggs through in vitro fertilization. Each could be grown for a while in vitro and then be tested for desired traits. Only an egg with all the traits desired by the parents would then be implanted in the mother. There are obvious drawbacks, not the least of which is the large number of fertilized eggs that are not selected. This option is not a viable alternative for many couples for religious reasons.

Another drawback is that selecting for a very large number of traits is close to impossible. Each gene desired at least doubles the number of fertilized eggs required. Certain traits are the result of many genes acting in concert, which could inflate egg requirements very quickly. Last of all, fertilized eggs must have one copy of each gene from each parent. Even with an infinite number of eggs a bad gene cannot be totally eliminated if one parent has two copies of that gene.

Genetic Manipulations

Genetic Manipulations are becoming common as a means of genetic engineering. There are many methods of introducing new genetic material into a cell or organism, or altering the existing material. Radiation and mutagenic compounds are able to reek havoc on DNA. Special viruses have been altered and put to use which can introduce new genetic material to an organism. Transposable elements, natures own gene shuffling tools, have been put to use moving genes around in cells and organisms. Gene Targeting is a way of replacing a specific gene with another within a cell.

These kinds of genetic manipulations are great for research with animals. Gene targeting seems to be the most precise way of altering known genes. Gene therapies often try to replace or repair defective genes in tissues where the genes are in use. Gene therapy does not usually alter the "germ line", that is the reproductive cells, so even if gene therapy corrects a problem, the problem can still be inherited by children.

Gene Therapy on the reproductive cells, or better yet, on a fertilized egg could be used to introduce whatever genes are desired into an organism, even a human, when they are still a single cell. With cloning technology, not even a fertilized egg is needed, just a cell that will grow in cell culture. This is where genetic engineering stands right now. It is technically possible to repair and/or replace any known gene, but it is not very efficient and requires a large number of cells, of which only a few will be properly repaired. The other limitation is the number of known genes.

The functions of all the genes are not known, only those of a very small percentage of the total genes in organisms such as humans. Research in animals is uncovering the functions of the precursors of human genes, and that research helps in determining the precise function of human genes, but research is proceeding slowly. There may come a time when we have the option of children who are Albert Einstien, Micheal Jordon and Bill Gates (or their female equivalents) roled into one, but not yet.

What's preventing genetic manipulation of all the known genes in human eggs? Cloning has not been demonstrated to work with human cells for one thing, but Doctor Richard Seed may be working on that right now. There may be public opposition to human cloning that is slowing research. The cost of genetic manipulations is relatively high and takes quite a while. Supply and demand may be the key. Demand for children guaranteed not to have any of the known genetic diseases is outweighed by the costs, but they will eventually meet somewhere in the middle as the number of correctable diseases rises and the costs fall.

I can envision special gene constructions just for the purpose of cleanly replacing disease genes with the functional versions. Libraries of functional and optimal versions of genes -within DNA constructs necessary to introduce them into cells- will likely be created soon by genetic engineering companies, if they have not been started already. I have my own ideas about what those constructions must include. Current gene therapies are very sloppy when it comes to altering genes, but I have some ideas on making it cleaner and perhaps more precise. I intend to share those ideas with the world from right here on this page some time soon.

True Genetic Engineering

What I would call true genetic engineering is the creation of whole new genes and proteins, or even new organisms. We understand the genetic code and can create random or specific proteins quite readily, but creating new proteins precisely for a given purpose -for example, to strongly catalyze a particular chemical reaction- is still beyond us. Research into the structure and folding of proteins may yield some answers. Mixing and matching of the components of known proteins and organisms may yet be mastered, but that is a large step beyond even the manipulation of known genes, but there is still much more beyond that.

Playing God!

Is substituting one gene for another or introducing functional genes, as in gene therapy, playing God? Is creating new genes, proteins and organisms playing God? Perhaps, but it is all possible within a certain set of rules that have been handed down to the human race by 4 billion years of evolution, or perhaps by the creator himself. The genetic code was probably decided quite early in evolution, being defined almost entirely before the first eukaryotic cells (cells with a nucleus) over 1 billion years ago.

It may be possible to one day change the genetic code, so that every sequence of three nucleic acids codes for a different amino acid. This would be possible through a relatively simple change in the sequence of DNA coding transfer RNA. Changing the sequence of all the other DNA so that it would recognize the new genetic code and produce functional proteins would be the hard part, but why stop there!

While we're at it we could replace the 20 amino acids that are included in the genetic code with all new amino acids. The current coding system of three nucleic acids per amino acid would allow for as many as 64 different amino acids. Think of the diversity of protein function possible with so much more variety! DNA itself could have more variety, how about 6 nucleic acids instead of 4. A three nucleic acid sequence could then code for 216 amino acids, or use just two nucleic acids to code for 36 different amino acids. Proteins could be right handed instead of left, DNA and RNA could spiral in the other direction, etc.

In fact life may be possible using entirely different chemicals than life here on earth, no DNA, RNA or protein as we recognize them. I actually think that's quite unlikely. The components of life are in and of themselves quite simple molecules, most of which would probably be used again if life evolved somewhere else, or was created artificially. Some of the elements of the process are most likely entirely random, such as the handedness of protein, and the direction in which the DNA helix rotates. The genetic code itself is probably random, and there are rare occurences of non-standard genetic codes still found on earth, such as in the DNA of some cellular organelles and certain bacteria.

That's as far as I can go on the subject of Genetic Engineering, but there are many ideas here that could be more fully fleshed out. As I come across more information and read about more of the research that's being done, I will update this page. If you come across more detailed information on the Internet covering any of the topics listed here I may be interested in linking to those pages. You may send e-mail to me, Arthur Kerschen

Some other Internet reading on Cloning and Genetic Engineering: