June 2005

Barbara J. King


Spirituality Explained? Reflections on Dean Hamerís The God Gene

The time is ripe for gene-based theories of spirituality. After all, we live in a country both saturated with religion and all hotted up about genes.

Sales of religious books soar while the publishing industry, generally, slumps. Religion and politics couple widely: intelligent-design advocates work to export evolution from the science classroom while Democrats work to import religion into their party platform. Three-star-decorated Army general Jerry Boykin publicly announced he knows his Christian god is real whereas the Muslim god is an idol, and adds that George Bush is in office because God put him there.

On the genetic side, it’s DNA 24/7. Genes explain (or so the media claim) everything from dread diseases to temperment types. Shy? Must be grandmother Millie’s blushing gene that skipped a generation. Got an urge to bungee jump, climb Kilimanjaro, or speed around on motorcycles? That’s Dad’s hot-rodder gene in a new risk-taking incarnation. And the legacy of Dolly the Sheep (1996-2003) lives on too. (Genetic duplicating is on my mind thanks to Ishiguro’s terrific Never Let Me Go, which I inhaled in complete happy absorption the same week that Korean scientists announced a new improved method for cloning human embryos.)

This climate propelled Dean Hamer’s The God Gene into some measure of prominence (cover of Time, October 25, 2004). Let’s deal with the title right away. Pretty unequivocal, no? The God Gene! Already on page 8, however, Hamer inserts a disclaimer: “There are probably many different genes involved, rather than just one. And environmental influences are just as important as genetics.” Hamer is nothing if not savvy: this measured estimation is too tepid by half for marketing a book (or making Time’s cover).

What are we to make of Hamer’s retreat from the bold confidence of his title? By invoking environmental influences, does he mean to embrace what anthropologists like me call a social constructionist explanation? That is, does he admit the importance of how we are raised and loved and guided, for explaining why humans everywhere tend to embrace some notion of God, gods, or spirits? (I get really riled when any cultural universal is automatically assumed to be an instinct; cultural factors can explain many universal human behaviors.)

Science writer and blogger Carl Zimmer is unsatisfied with Hamer’s page 8 retreat. He suggests a title that more accurately reflects the book’s contents: A Gene That Accounts for Less Than One Percent of the Variance Found in Scores on Psychological Questionnaires Designed to Measure a Factor Called Self-Transcendence, Which Can Signify Everything from Belonging to the Green Party to Believing in ESP, According to One Unpublished, Unreplicated Study.

To fully understand what Zimmer means by his mock title, it’s important to see the distinction Hamer makes between religion and spirituality. Religion is “belief in a particular God, frequency of prayer, or other orthodox religious doctrines or practices.” Hamer isn’t interested in measuring a tendency to be religious, as it turns out: “If
our intent had been to measure religiousness rather than spirituality,” he writes, “…[w]e might have explained how often people attended religious services, for example, or whether they took their children to Sunday school.”

In other words, Hamer conflates religion with a narrow set of institutionalized practices. This is problematic for a huge number of reasons I won’t enumerate here, since Hamer’s focus is on spirituality. Spirituality is self-transcendence, the capacity for experiencing the self at one with the world, and can in turn be measured via a fine-tuned questionnaire that focuses on self-forgetfulness, transpersonal identification, and mysticism. All this jargon aside, the key point for Hamer is that once you’ve got the questionnaire answers, all you need next is... DNA!

Science geeks (is there a geek gene?) can consult the book for the details of Hamer’s research design. Suffice to say that an impressive 447 pairs of siblings submitted to Hamer’s self-transcendence testing and some donated their DNA. From this large group, Hamer found a higher-than-expected correlation within pairs: sibs were more similar in measures of self-transcendence than they are expected to be. Hamer concedes that this is no proof of a genetic basis for spirituality “since a positive correlation could, in principle, be due to genes, shared environments, or a combination of both.”

That pesky shared environment again! How does Hamer deal with it? Not very well. First he figured out which of his study subjects have which of two versions -- alleles in technical language -- of a specific gene called VMAT2 (a gene that helps regulate the emotions we feel everyday). Then Hamer ran more tests to figure out if one of the two alleles correlated better with high scores on the self-transcendence scale. “We hit pay dirt,” Hamer says. One of the two alleles -- “the spiritual allele” -- correlated with self-transcendence.

Next, and crucially, Hamer narrowed his focus to a contrast within sibling pairs only. Why? Not only do siblings have the same economic and racial-ethnic backgrounds, they “go to the same schools and the same churches. They even have the same parental and grandparental influences.” In other words, by comparing only same-sex sibs to each other, Hamer believes he kills off the shared-environment explanation.

Oh for space enough and time to debunk Hamer’s assumptions! Possibilities for differential environmental influence on, say, two sisters of different ages, approach infinity. One sister’s younger years may coincide with a period of parental marital harmony while the other’s may intersect with a prolonged divorce that stresses the whole family. Or perhaps one sister merely encounters a certain inspirational teacher or well-loved book that the other does not. Non-shared experiences like these heap contingency upon contingency as each girl develops. In the end, the two sisters may essentially grow up in divergent emotional environments -- and as a result make very different choices about the role of spirituality in their lives.

The heaviest ammunition against Hamer’s argument is supplied by his own statistics. Of the 106 pairs of same-sex siblings who had different VMAT2 alleles, 55 fit the predicted pattern: the sib with the spiritual allele scored higher. Hamer admits this is a weak trend at best, but asserts anyway that the spiritual allele may alter how its owner’s brain processes aspects of experience related to spirituality, and how those experiences actually feel. Then he drops a bombshell: the spiritual allele raised self-
transcendence scores by less than 1% of the total variance in the sib sample.

Zimmer’s faux title exposes the shoddy scholarship at the core of this book. Hamer’s 11th-hour admission that “just because spirituality is partly genetic doesn’t mean it is hardwired” is too little, too late. If there were a literary analog to the emperor with no clothes, surely it would be The God Gene. Years ago, Hamer announced a gene for homosexuality. That “discovery” has been not just challenged but repudiated (see, e.g., http://www.fathersforlife.org/gay_gene.htm) Maybe Hamer needs to find a gene for recognizing fiction masquerading as science.

-- Anthropologist Barbara J. King is writing a book on the prehistory of religion.