Transfer of genetic material and production of new traits in nature takes millions of years to be achieved.
If this is sought to be achieved in a very short period it amounts to short circuiting the normal process and the consequences could be really hazardous. When an individual is fashioned out of natural process it will be a package of both weakness and strength.
If we were to tinker with this process it would naturally disturb the fine tuned balance and relationship that is existing between the organisms since millions of years.
3. The intended benefits of genetic engineering research can be actually achieved through other research methodologies.
To achieve these goals one need not resort to such dangerous techniques Ike genetic engineering. The benefit of genetic engineering research does not justify the cost (not just in terms of money) involved.
4. With the kind of diverse political set up prevailing in different countries of the world where dictators, fundamentalists etc still have a very powerful say, this technique can definitely be misused and there is every possibility that these people might unleash a biological warfare on countries that they consider inimical to them.
For instance water bodies of a country could be infected with new versions of pathogens or their environment might be sprayed with pathogenic microbes. All these possibilities should make one think whether it is worthwhile indulging in this kind of research.