The ethics of genetic combinations
SINCE ancient times, we have been aware of several basic ideas of heredity. Plants and animals with superior characteristics were isolated and multiplied. Human mating practices were restricted to exclude incest, as well as matings outside specific defined groups.
In the 1970s, genetics received a real fillip with the advent and the widespread use of the so-called recombinant DNA technology (R-DNA). This technology provided extremely powerful tools for dissecting the structure and functions of the genes and the many programs involved in inheritance; to isolate individual genes and transfer them to new hosts and thus generate novel types of organisms. These techniques have revolutionised genetics and indeed unified biology. Novel concepts, techniques and products are revolutionising health care, agriculture, forestry, food processing, forensic science and even health insurance, and the way we look at the world.
The success and potential of genetics helping us gain knowledge about our make-up and in altering our society and environment has also created understandable concerns in the public mind. Several questions with ethical, political and economical ramifications have been raised. All this was reflected in the 17th International Congress of Genetics, held in 1993, in Birmingham, UK, whose main theme was "Genetics and the Understanding of Life".
Several presentations seemed to vindicate William Bateson's observations made in his inaugural address in 1908 at the 5th Genetical Congress in London. Bateson said, "There is no lack of utility and direct application in the study of genetics. If we want to raise mangoes that will not run to seed or breed cows that will give more milk in less time, or milk with more butter and less water, we can turn to genetics with every hope that something can be done in these laudable directions".
The opening address of the 17th Congress, "Should genes be screened", by Nobel Laureate Max Perutz focused on the pros and cons of using R-DNA techniques for gene screening. There seem to be no general rules about the advantages or disadvantages of genetic screening. To reduce the incidence of genetic disorders, Perutz advocated genetic counselling and termination of pregnancy
"However, there is fear that, under mainly commercial pressures, this facility may be misused," cautions Perutz. He nevertheless adds, "Medical benefits of screening for the most crippling inherited diseases and predispositions to certain cancers, outweigh the social dangers and moral objections. Hence, everyone has the right to be given the information he asks for about his own genetic make up and that of his new-born children but no one has a right to information about the genetic make up of other people and their children".
Molecular approach A common topic of discussion was the widespread use of modern recombinant DNA techniques. Even in areas once considered the domain of traditional genetics, there was a high degree of molecular approach. "Chemosensory genetics of the fruit fly" by Obaid Siddiqi from the Tata Institute of Fundamental Research, Bombay, aroused much interest. Many scientists have marvelled at the fly's well developed sense of smell as it homes on to bananas and wondered how this "humble" fly manages this feat so elegantly. They reasoned the understanding of this process in the fly may give some insight into the functioning of the human brain.
Siddiqi's laboratory has identified several genes controlling the development of chemosensory organs in this fly. Mutations of these genes have been used to analyse the mechanisms by which the neuronal circuits for olfaction and taste are formed. Eventually, Sidddiqi hopes to unravel the chemosensory map in the brain of the fly, which seems to be responsible for its keen sense of smell.
However, the biggest challenge facing the geneticists is to find ways to feed the world. Several plant geneticists made a strong plea for diverting more funds and effort to research in basic plant genetics, especially on rice and pulses, which are staple diets of people in developing countries. M S Swaminathan, founder of the Centre for Research on Sustainable Agriculture and Rural Development, Madras, emphasised the importance of maintaining biodiversity and the role of rural women in several parts of India in preserving local plant varieties. One of his pet projects is the creation of bio-villages where there will be a harmonious blend of biotechnology and traditional methods employed by farmers so that small farmers will not be burdened with unsustainable techniques.
The meet was not without the kind of excitement that one associates with genetics. But the many benefits of genetics also seem to arouse fears, often unjustified in the minds of public. Thank God the organisers seemed aware of it.
Bskhtaver S Mahajan is with the Homi Bhabha Centre for Science Education, Tata institute of Fundamental Research, Bombay.