The 1970's are witnessing a scientific breakthrough of potential significance, comparable to the splitting of the atom in the 1940's and the landing of human beings on the moon in the 60's. This new knowledge, known as recombinant DNA research, enables man to combine the genes of unrelated species and introduce these hybrid genes into a live organism, where they become active.
Before examining the religious implications of this development, we will describe the continuing gene re combination experiments and the lively debate they have touched off among both scientists and nonscientists.
A characteristic property of living matter is its potential ability to re produce itself. The information required for faithful reproduction re sides in the chromosomes of the cells—the building blocks of living matter. This genetic information is divided into units called genes. Each gene contains a particular piece of specially coded genetic information regarding the structure either of a protein molecule or of a small ribonucleic acid molecule or of some control function in the biosynthesis of both nucleic acids and proteins.
Genes control all of the physical attributes of an organism by con trolling protein molecules—the molecules that perform most of the work within the cell, and constitute a large portion of its structure. During growth, the genes inside each cell double in number so that following cell division both resulting cells receive the identical number of genes. This holds true for all forms of living matter from the simplest to the most complex.
In the early 1940's O. Avery, of Rockefeller University, discovered that the chemical identity of genes was deoxyribonucleic acid, commonly abbreviated as DNA. De tailed structural analysis of this sub stance revealed that DNA ordinarily occurs as a double molecule—two very long molecules intertwined around each other in a "winding staircase" pattern. The genetic in formation carried by DNA is deter mined by the particular sequence in which the building blocks of DNA, the nucleotides, occur. The two strands making up DNA are not identical in their chemical make-up, but they contain identical genetic in formation, somewhat like the positive and negative plates of a photo graph.
As chromosomes double inside the cell prior to cell division the two strands of the DNA molecule separate and the original positive strand acquires a new negative strand. Likewise, the original negative half of DNA is joined with a newly made positive strand. In this fashion each new cell inherits the exact number of genes of the original, and the species' characteristics are perpetuated.
In nature it happens occasionally that extra pieces of foreign genetic material find their way into cells. However, cells are not defenseless against this intrusion. Each cell has a detachment of internal-security agents, known to scientists as restriction enzymes. (Enzymes are special protein molecules that pro mote specific chemical conversions.) The restriction enzymes carefully probe the structures of any newly arrived genetic material. If it turns out to be of foreign origin, the restriction enzymes rapidly degrade and inactivate it. The universal and ubiquitous presence of restriction enzymes is one of the main barriers between inter-species reproduction.
In the early 1970's molecular biologists discovered that restriction enzymes did not degrade foreign DNA molecules randomly, but broke the strands at very specific sites. In fact, these enzymes break one strand only at a particular nucleotide sequence that they are programmed to recognize; the second strand is cleaved at a different site not far removed. This attack on the foreign DNA converts the original, long, double-stranded DNA to several shorter pieces with identical frayed ends. These ends can fit each other in the manner of a jigsaw puzzle.
If these short pieces of DNA molecules are placed in a test tube and treated by appropriate chemical means, splicing of these units occurs. This crucial discovery gave rise to the field of recombinant DNA research. Scientists were quick to realize that if one takes two separate types of DNA, each treated with the same kind of restriction enzyme, and applies the splicing technique, the end products are hybrid DNA molecules.
Most DNA recombination re search to the present has involved Escherichia coll. This harmless microorganism, originally isolated from the human colon, is one of the most studied and best understood organisms. Scientists have learned that hybrid DNA is not degraded when introduced into special variants of E. coli which have defective restriction enzymes. Genes of foreign origin thus introduced can express themselves in the host cell.
As scientists began working with this system they realized that highly dangerous varieties of E. coli and other microorganisms might be produced by such techniques. For ex ample, if the gene that carries the codes for the neurotoxin of botulism in the organism Clostridium botulinum were to be spliced into E. coli we would have a truly deadly organ ism, since less than a millionth of a gram of botulinum will kill a person.
Consequently a number of concerned scientists published a plea in the Proceedings of National Academy of Sciences to halt these kinds of experiments. Later a conference composed of 140 scientists from 16 countries convened in Asilomar, California, for the purpose of discussing guidelines in this type of work. Not everyone agreed on the magnitude of the danger involved, but there was no doubt in anyone's mind that definite risks were involved. The conference agreed to formulate guidelines for recombinant DNA research by which the potential risks would be matched by appropriate containment measures. Unfortunately, the magnitude of danger involved is totally unknown, and this is the point around which vigorous debates have sprung up both among scientists and informed nonscientists.
The majority of scientists feel that the risks are minimal if proper containment techniques are followed, whereas the potential benefits are incalculable. These individuals see this technique as the first step toward being able to replace faulty genes in individuals with inborn errors of metabolism, such as those suffering from sickle cell anemia, phenylketonuria, hemolytic anemia, et cetera.
In agriculture, the incorporation of nitrogen-fixing genes into plants would do away with the need for nitrate-containing fertilizers. Recombinant DNA techniques could even contribute to the solution of the energy crisis by the construction of easily grown microorganisms that could convert water to hydrogen gas, using sunlight as the energy source.
But one cannot ignore the minority opinion concerning recombinant DNA research. It raises the specter of accidental or deliberate construction of organisms with unknown or unpredictable behavior, especially in large scale use of these organisms for industrial or medicinal purposes. The time when we are in complete control over any microorganism is certainly not here, as demonstrated by the outbreak of the so-called Legionnaire's disease in Philadelphia, now fairly conclusively shown to have been caused by hitherto unknown microorganisms.
The most extensive current guide lines for this type of research have been formulated by the National Institutes of Health. All research funded by the U.S. Government must abide by these guidelines, as of July, 1976. These guidelines spell out various levels of physical and biological containment, including rigorous systems of hoods, airlocks, and other facilities, as well as limiting the types of strains of E. coli that can be used as recipients of hybrid DNA. Strains permitted for such use would be those unable to survive outside the sheltered laboratory.
Since not all research in this country falls under the sponsorship of the National Institutes of Health, the United States Congress is currently considering legislation to make it a Federal offense to perform experiments involving recombinant DNA without adequate safety measures.
Christians living amidst this controversial development will naturally ask themselves, What is the meaning of all this? Does tampering with genes amount to rebellion against God's plan for nature?
In the Bible, following the Creation account we find that the Lord commanded man: "Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion . . . over every living thing that moveth upon the earth" (Gen 1:28). Thus the Creator gave mankind a mandate to explore this world, and to use his discoveries for the benefit of mankind. Scientists have found ways to hybridize plants, obtaining new varieties of fruits, vegetables, flowers, et cetera. Man also has been successful in producing very useful strains of horses, sheep, cattle, dogs, et cetera, through controlled breeding. All these activities involve genetic engineering of sorts. If carried to their ultimate potential, recombinant DNA techniques would enable man to accomplish such activities more efficiently and to a greater extent.
It might be argued that new life forms that might emerge as a result of the application of this method, would not be offensive to the Creator so long as they did not bring suffering to any existing life form, nor result in the degradation of humanity. Thus, engaging in recombinant DNA research itself does not appear to be rebellion against God.
Nevertheless, like many other discoveries, recombinant DNA work can be used for evil purposes. This was, in fact, the basis of the alarm sounded by the scientists pioneering in this field. The great rebel, Satan, used genetic engineering, perhaps of the recombinant DNA variety, when he went about producing noxious and poisonous plants early in this earth's history (SDA Bible Commentary, vol. 1, p. 1086). In the antediluvian world, genetic manipulation led to the appearance of degraded forms of species, and to confusion among the created kinds. This sin was the greatest among those that led to that world's destruction (Ellen G. White, Spiritual Gifts, vol. 3, pp. 64, 75).
The current mood among scientists is one of opposition to excessive Federal intervention and regulation. They down-play the potential dangers of recombinant DNA re search, citing recent data on this subject that would indicate that much of the previously expressed fears have no factual base (editorial by P. Abelson, "Recombinant DNA," Science 197, Aug. 19, 1977). But the Christian perspective should call for continued or even increased vigilance and caution along these lines of research. It should applaud the NIH guidelines already implemented and should encourage their continuance.
Many Christians are amazed at the extent to which the Creator has allowed sinful man to pry into the secrets of creation. Among the possible reasons for God's forbearance on this point is the hope that man kind, after considering the almost unfathomable intricacies he is currently discovering in nature, will come to the obvious conclusion that a loving and wise Creator does indeed exist.