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Playing God has its downside
(November 2003)

With the deciphering of human, animal, insect, and plant genomes, and with amazing new technologies, we have the capacity to insert foreign genes into people, animals, and plants. The potential advantages are enormous. Plants can be made to resist frost, fight off pests, grow in salty conditions or in the desert. Potentially, the scourge of vitamin A deficiency in many less affluent countries of the world can be eliminated. Those with disease due to missing or abnormal genes can be given functioning genes. The potential is mind boggling. But, inserting genes from the same or different species and thereby changing the characteristics of plants, animals, or even people is, in a sense, playing God and with all the potential for good, there is potential harm - and, above all, there is the unexpected. Two articles in the journal Science illustrate the point.

The first concerns two children with a terrible, fatal disease called SCID, standing for severe combined immunodeficiency. This is a genetic disorder that becomes apparent shortly after birth, and is complicated by severe infections. These children can be given a functioning immune system that prolongs life (usually good quality life) by inserting a gene carried on the back of a virus that is first made unable to multiply or cause damage. The assumption is that the disabled virus (whose function is to carry the gene to be inserted) can do no harm. But, in two children after what appeared to be a successful gene treatment, both developed a form of leukemia. It turned out to likely be due to the fact that the disabled virus inserted itself next to a gene that promotes cancer and apparently activated that gene. The authors point out that this unexpected complication of gene treatment requires reevaluation of risks of the treatment. For the inactivated virus to start a train of events that led to cancer was a real and unpleasant surprise.

The other article examined spread from a genetically altered rapeseed (the source of canola oil) to wild growing rapeseed of a related species type. The authors found that cross fertilization occurred frequently both locally and at a considerable distance, spreading the genetically created trait into the environment. Previous analyses had concluded, in essence, that there was no problem. This cross fertilization by itself does not imply harm, but it does indicate, and indicate strongly, that we had better not be glib about adding a gene to a plant to do something advantageous and assume that the added gene will not disseminate into the environment and give an advantage to plants we do not want to become dominant. Thus, if we give a food producing plant a gene that protects it from a pest, that protection could spread to nearby weeds. A species of corn if given a growth advantage could wipe out other species, and thereby reduce healthy biodiversity.

We should be very cautious about adding genes to a given species or across species, and we had better be prepared for the unexpected.

Playing God with gene treatment or genetic modification can accomplish a great deal for individuals and for societies. But, it also, in some situations, has the capacity to harm individuals and, under certain circumstances, it can do terrible things to the ecology and the environment. Adding genes for beta carotene and vitamin A to food staples in certain developing areas of the world would seem to have virtually no downside. On the other hand, adding a gene to a plant to protect it from pests might appear advantageous, but it could have disastrous effects if it spread widely in the environment.

The bottom line is that we should move ahead vigorously with gene research and application of that research, but the science must be accompanied by caution, wisdom, and a determination above all not to do harm.

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