The belief in and attempt to manipulate the supernatural is widespread throughout humanity. Although the particular content of any people’s religious or spiritual beliefs is dependent on their specific environment, lifestyle, social configuration, and history, the presence of spiritual or supernatural beliefs of some sort in virtually every society suggests that there may be a biological basis to the capacity to believe. Dean Hamer, a biologist and head of the genetic unit of the National Cancer Institute, claims that he has discovered at least one of the biological traits that fosters spiritual belief: a gene responsible for the production of one of the chemicals used to regulate emotion in the brain.
The God Gene (2004) is the title of Hamer’s book presenting his research on the relationship between genes and spirituality. Specifically, the “god gene” refers to a particular variant of the gene that codes for protein VMAT2 (vesicular monoamine transporter 2), which plays a role in regulating levels of serotonin and dopamine in the brain. In Hamer’s research, subjects whose VMAT2 gene contained either one or two molecules of cytosine generally scored much higher on tests designed to measure spirituality than those with only adenine in the same position.
In the course of research on smoking and addiction, Hamer administered a set of psychological tests to 1,388 subjects, including a set of questions based on the research of psychiatrist C. Robert Cloninger intended to measure a subject’s self-transcendence. Cloninger’s test measures three qualities: self-forgetfulness, the tendency to focus so intently as to lose track of the world around oneself; transpersonal identification, the feeling of connectedness to the universe and its inhabitants; and mysticism, the willingness to believe in things not approachable through reason. The test is intended to measure individual spirituality, divorced from the particular content of organized religious belief and orthodoxy.
Hamer’s findings suggested a strong link between the presence of the cystosine variants of the VMAT2 gene and spirituality as measured by Cloninger’s test. In test cases where one sibling had a cytosine variant, almost all scored markedly higher for self-transcendence than their non-cytosine-bearing siblings. After correcting for other possible influences, Hamer was convinced that a significant correlation existed. What was left was to propose a mechanism by which VMAT2 might influence spirituality.
VMAT2 regulates the brain’s use of monoamines, chemicals that play a crucial role in both motor control and emotional status. Among other things, monamines and, thus, VMAT2 play an important role in coordinating the responses of the thalamocortical complex, responsible for perception and reflection, and the limbic-brain stem system, which produces emotional responses. During periods of heightened spiritual awareness, the Buddhist’s meditative state, for instance, or the shaman’s trance, the thalamocortical system draws more and more of the brain’s blood flow and energy to itself, reducing the efficacy of the other centers of the brain in a process called deafferentation. One system affected by deafferentation is the part of the brain responsible for locating the body in space. As more and more energy is drawn by the thalamocortical system, these other parts of the brain send “panic signals” to the limbic system. The limbic system, in turn, signals the thalamocortical system, forcing it to draw even more energy to itself and setting up a feedback loop in the brain that produces a greater and greater feeling of detachment from or expansion beyond the body, a situation easily understood by most as describing a mystical experience. According to Hamer, those with the cytosine-holding variants of the VMAT2 gene might find it far easier to produce these kinds of feedback loops than those with the adenine-bearing variant, making them more open to mystical experiences.
Hamer himself notes that VMAT2 likely plays only a small role in spirituality, noting that spirituality is too complex a phenomenon to be reduced to a single gene or even a single neurological process. But even taking this into consideration, his work as it stands presents a number of difficulties. The first is the way in which he, following Cloninger, defines spirituality itself. Cloninger based his tests on a study of people he considered to be extremely spiritual—Albert Schweitzer, Mahatma Gandhi, Catholic saints, Buddhist monks—then chose the traits that he felt marked them as spiritual. It is hard not to wonder if his criteria might not represent a Western notion of individual spirituality that may not have much meaning in significantly different cultural contexts. Although the tests have been administered to Americans from a variety of ethnic backgrounds, the fact remains that they have yet to be administered outside of the United States and may only reflect widely shared Western notions of spirituality. One has to ask if statements such as “I am fascinated by the many things in life that cannot be scientifically explained” or “I believe that miracles happen” would tell us anything useful about the spirituality of, say, an Amazonian hunter-gatherer or South Pacific horticulturalist.
Hamer’s hypothesis is further burdened by his uncertainty about how to weigh religious behavior as evidence. While at some points, Hamer insists on the noncommensurability of religion and spirituality, at others, he relies primarily on aspects of religious behavior, for instance, the role of religion in fostering and maintaining social solidarity, to ground his argument for the evolutionary importance of the god gene. In the first case, religion is opposed to spirituality, reflecting contemporary usage that associates “spirituality” with the individual and “religion” with the community. In the second, religion is presented as interchangeable with spirituality, so that the Venus figurines of Eastern Europe or the cave bear clans of Paleolithic France are seen as evidence of early human spirituality.
Ultimately, Hamer’s work presents more questions than answers. While his fundamental assumption— that regardless of what we believe, there must be some neurological structure within which believing occurs—is sound, his conclusions are broader than his research and evidence support. Basing universal conclusions about human biology on culture-specific evidence seems hasty and even dangerous. At best, he has produced a very preliminary hypothesis about one possible factor in spiritual behavior, one that demands much more rigorous testing.
- Cloninger, C. R. (2004). Feeling good: The science of well-being. Oxford: Oxford University Press.
- D’Aquili, E. G., & Newberg, A. B. (1999). The mystical mind: Probing the biology of religious experience. Minneapolis, MN: Fortress Press.
- Hamer, D. (2004). The God gene: How faith is hardwired into our genes. New York: Doubleday.