The apparent growth in knowledge regarding human nature cultivated by genetic research leads some religious thinkers to review their inherited anthropologies. Most theologians see the field of genetics as a challenge requiring response; a few see new genetic knowledge as a complement to long standing religious insight. Distinctively theological issues are few and are frequently embedded within the more plentiful and visible issues of ethics and public policy. Theological issues will be taken up immediately; ethical issues surrounding cloning and stem cell research will follow.
The first theological concern is genetic reductionism. Reductionism poses a theological threat everywhere in modern science. The form it takes in genetics is the vague cultural belief that “it’s all in the genes.” In the laboratory, methodological reductionism is necessary to foster research into gene function, but a threat comes with ontological reductionism and surmises that all of what constitutes human nature is reducible to the genes. During the early years of the Human Genome Project, DNA was described by some scientists as the “code of codes” or the “blueprint of humanity.” Such biological reductionism seems to leave no room for independent influence on the part of spirit or culture, the dimensions wherein most religious traditions work.
A second and related concern is genetic determinism. If “it’s all in the genes” and the DNA is the blueprint of who human beings are, then genes move into the position of determiners of human nature and human value. In the historical struggle between nature and nurture in the minds of intellectuals trying to explain human complexity, the new breed of genetic determinists stake their claim on nature. Relatively few molecular biologists advocate strong genetic determinism, whereas behavioral geneticists and sociobiologists reinforce it.
Molecular biologists and philosophers who oppose an exclusive genetic determinism frequently appeal to two part determinism: genes plus environment. Some theologians locate human freedom in three part determinism: genes, environment, and the human self or person. In the latter case, the human self is emergent; the self is not reducible to either biological or environmental influences. Divine action in the human reality here is said to be holistic—that is, present to all three dimensions of biology, environment, and person.
A third and related concern is neo-Darwinian evolution. Nineteenth century Darwinism employed natural selection as the mechanism for explaining evolutionary change over time. Twentieth century neo-Darwinists such as Fransisco Ayala or Stephen Jay Gould add genetic mutation to the theory, adding detail to the manner in which natural selection works. Sociobiology extrapolates on neo-Darwinism by attempting to explain all of human culture including religious belief in terms of biological determinism. Sociobiologists (sometimes called evolutionary psychologists) contend that human culture is on a leash, a short leash, held by a genetic agenda. That agenda is the self-replication of genes using the human species as its vehicle.
Human culture is structured so as to encourage reproduction and, hence, the perpetuation of genes. Human religion and human morality, whether theologians know it or not, is reducible to the agenda of selfish genes. Those theologians who are attempting to incorporate sociobiology into their religious vision feel they must justify human transcendence of biology and the emergence of soul or spirit. Philip Hefner’s theological anthropology, for example, argues that through evolutionary processes the genes have determined that we humans would be free.
Some Christology’s contend that Jesus marks a significant advance in evolutionary history, because with the Nazarene a precedent-setting life is led that transcends the selfish genetic agenda, and the possibility is opened for self-sacrificial loving. In contrast, some Muslim scholars find they must simply reject neo-Darwinian evolutionary theory because it makes no room for human spirit and because it fails to cohere with the anthropology of the Qurhan.
In summary, the theological community is accepting of the methodological reductionism within molecular biology that functions to yield advance in scientific research. However, theologians resist philosophical extrapolations that tend toward ontological reductionism or genetic determinism. Reductionism and determinism are insufficient, say theologians, to explain spiritual reality or ethical transcendence. Theologians defend human freedom and moral transcendence whether it complements the science or requires abandoning the science.