Medicine, Health Care, & Ethics: Catholic Voices

8. Genetics and Ethics: Questions Raised by the Human Genome Project - Kevin D. O’Rourke, O.P.

Chapter 8 Genetics and Ethics Questions Raised by the Human Genome Project Kev in D. O’Rour ke, O.P. Few enterprises have been as grand as the Human Genome Project (HGP). According to its leaders, the project is “an ambitious effort to understand hereditary instructions that make each of us unique.”1 It is intended “to find the location of the 30,000 or so human genes and to read the entire genetic script, all three billion bits of information, by the year 2005.” Researchers have announced that, although some chores remain, the task of identifying and sequencing the human genome is substantially complete. The ultimate goal of the HGP is to decode, letter by letter, the exact sequence of all three billion nucleotide base pairs that make up the human genome. Researchers hope this knowledge will lead to new technologies that can, first, identify defective genes, and, second, either neutralize their debilitating qualities or replace them entirely with “good genes.” In the future, genetic science may even be able to wipe out some diseases altogether. The HGP’s potential benefits seem endless. In the past, physicians diagnosed an illness as the result of a clinical examination , confirming it through biomedical testing. Those procedures are becoming obsolete, according to the HGP’s leaders: 211 This article originally appeared in Health Progress (March–April 2001): 28–32. Copyright© 2001 by the Catholic Health Association. Reprinted with permission. On the horizon is a new era of molecular medicine characterized less by testing symptoms and more by looking to the most fundamental causes of diseases. Rapid and more specific diagnostic tests will make possible earlier treatments of countless maladies. Medical researchers will be able to devise novel therapeutic regimens based on new classes of drugs, immunotherapy techniques, avoidance of environmental conditions that trigger disease, and even replacement of defective genes.2 Francis S. Collins, M.D., the HGP’s director, has long maintained that medicine would make amazing strides as a result of genetic research. Some of the developments Collins predicted are already in motion. They include the following: • Each year clinical labs in this country perform millions of tests aimed at detecting potential or actual diseases caused by genetic defects. • Newborn infants are screened for sickle cell anemia, a metabolic illness called phenylketonuria, and congenital thyroid diseases. • Other tests reveal whether people predisposed by family history to develop cancer have in fact inherited dangerous genetic mutations. Early detection of such genes allows people to begin therapy before symptoms occur. Genetic therapy for potential diseases discovered through genetic testing may be applied in one of three different ways: through splicing into human cells a healthy gene to displace the defective gene, by administering pharmaceuticals containing altered cells, or by stifling harmful genes by interfering with their protein production. Still, we know that, although genetic makeup determines human physiology , it contributes only a predisposition to human behavior.3 Human personhood “is embodied intelligent freedom, with many levels of human activity most clearly manifest and definable by its maximum activity, the power to integrate these activities.”4 Collins has borrowed the words of another intrepid scientist, Copernicus, to suggest that the HGP itself may be part of God’s plan: “To know the mighty works of God, to comprehend His wisdom and majesty and power, to appreciate the wonderful working of His laws, surely all this must be a pleasing and acceptable mode of worship to the Most High to whom ignorance cannot be more grateful than knowledge .”5 212 Kevin D. O’Rour k e Genetic Screening and Stem Cell Therapy Two dramatic applications of genetic knowledge have already made news. Preimplantation Genetic Screening One news story concerned a six-year-old Colorado child who had been born with Fanconi anemia, a genetically caused disease that normally results in death at an early age.6 Her parents sought advice from medical scientists familiar with the illness. The scientists suggested that if the parents were to have a second child without the defective gene, that child’s blood might be transfused into their daughter and save her life. Because both parents had the Fanconi gene, their chances of producing a child who did not have the illness were only one in four. But the scientists were able (before implantation) to examine the newly conceived embryo, select from it a totipotent cell (one capable of generating a complete organism ) that did not have...