Genes contribute to religious inclination

| 121 Comments | 3 TrackBacks

New Scientist reports on the findings of a study on the impact of genes on religious inclinations

Genes may help determine how religious a person is, suggests a new study of US twins. And the effects of a religious upbringing may fade with time.

Until about 25 years ago, scientists assumed that religious behaviour was simply the product of a person’s socialisation - or “nurture”. But more recent studies, including those on adult twins who were raised apart, suggest genes contribute about 40% of the variability in a person’s religiousness.

But it is not clear how that contribution changes with age. A few studies on children and teenagers - with biological or adoptive parents - show the children tend to mirror the religious beliefs and behaviours of the parents with whom they live. That suggests genes play a small role in religiousness at that age.

Now, researchers led by Laura Koenig, a psychology graduate student at the University of Minnesota in Minneapolis, US, have tried to tease apart how the effects of nature and nurture vary with time. Their study suggests that as adolescents grow into adults, genetic factors become more important in determining how religious a person is, while environmental factors wane.

The study can be found in Journal of Personality (vol 73, p 471)

The title of the paper is:

Genetic and Environmental Influences on Religiousness: Findings for Retrospective and Current Religiousness Ratings

by Laura B. Koenig, Matt McGue, Robert F. Krueger, Thomas J. Bouchard Jr

Abstract Estimates of the degree of genetic and environmental influences on religiousness have varied widely. This variation may, in part, be due to age differences in the samples under study. To investigate the heritability of religiousness and possible age changes in this estimate, both current and retrospective religiousness were assessed by self-report in a sample of adult male twins (169 MZ pairs and 104 DZ pairs, mean age of 33 years). Retrospective reports of religiousness showed little correlation difference between MZ (r=.69) and DZ (r=.59) twins. Reports of current religiousness, however, did show larger MZ (r=.62) than DZ (r=.42) similarity. Biometric analysis of the two religiousness ratings revealed that genetic factors were significantly weaker (12% vs. 44%) and shared environmental factors were significantly stronger (56% vs. 18%) in adolescence compared to adulthood. Analysis of internal and external religiousness subscales of the total score revealed similar results. These findings support the hypothesis that the heritability of religiousness increases from adolescence to adulthood.

3 TrackBacks

Those Minnesota behavioral geneticists are at it again. Thomas Bouchard, Laura Koenig, Matt McGue and Robert Krueger have a new paper in The Journal of Personality about the heritability of religiousness that a lot of people have been talking about.... Read More

Hey, nice genes! from The Holowach Blog on March 18, 2005 3:04 AM

A more conclusive study would focus on identical and fraternal twins who were separated at birth... Read More

Hey, nice genes! from The Holowach Blog on March 18, 2005 3:08 AM

A more conclusive study would focus on identical and fraternal twins who were separated at birth... Read More

121 Comments

Interesting post. Helps explain why I have become religious. If there is a gene for religiosity, then the implication is that it is an evolved trait. I can see the evolutionary advantage of religion in a species that survives best in complex social groups. That is why I don’t think religion is useless.

Katarina Wrote:

If there is a gene for religiosity, then the implication is that it is an evolved trait.

First of all, the researchers found that a propensity for religous belief is heritable. They are far from finding a “god gene.” They don’t even have god QTLs yet. Heritability is not a metric I would put much weight in, especially in natural populations where environmental variation is so great.

Secondly, even if religiosity is heritable, and if there are certain alleles that lead to more religious behavior, they may or may not have evolved for that particular function. Their role in “godliness” could be a byproduct of some other physiological function under selection. Before we can start talking about genes for religiosity evolving under natural selection we should get some better evidence that there are such genes.

RPM: I was merely throwing out a hypothetical. If you are not interested in talking about it, fine. But I agree with what you say, it is unlikely to find a gene for religion, there being so many religions first of all, and secondly, so many motives for becoming religious. No, it would be difficult to put a finger on the gene or set of genes for such a broadly defined behavior.

Makes sense to me. I have always had a suspicion that original sin was encoded in our genes. I bet if Augustine was around, he’d agree.

Imagine that David, a single mutation may make someone free of original sin.

I’m going to make my standard point that “heritablility” is not the same as “heritable.” Heritability is a measure of the proportion of the variation of a trait that is due to genetic variation. Fitness traits, for example, can be completely determined by genetics, but still show zero heritability because they have zero genetic variation.

Reed A. Cartwright,

Would you expand on your comment? I don’t understand why fitness traits have no genetic variation.

Isn’t the Island of Dr. Moreau based on that idea? Cool movie.

Reed A. cartwright,

Would you please explain why fitness traits have no genetic variation? I am not challanging this, I just don’t understand.

I don’t see any problem with “religiousness” being heritable and favorable. Although “having a predisposition to being religious” would probably be a better term. Aspects of a person’s psychology (perhaps being more willing to uncritically accept things that make them feel better) could be under genetic control. These traits could be favorable for all sorts of reasons, however recall that over the past few thousand years, and probably longer, people have been persecuted and killed for not holding a particular set of religious beliefs. Surely that would have lead to selective pressure against people who were stubbornly anti-religious. In the end though why people are or aren’t religious is going to be exceedingly complicated.

Sorry about the double post.

What about studies that have pointed to the overall better health and longevity of religious people? Surely that would be an evolutionary advantage.

http://www.cbsnews.com/stories/2002[…]327496.shtml

Say there was found an atheist gene. Hypothetical thought experiment here. Say it was discovered that there was a single gene which, getting a homozygous pair of them made the person an atheist 99% of the time. My thought experiment question is, would fundamentalists support abortion when the fetus had that gene situation?

Could it be that people who have a better health are more likely to also be religious due to a third causal factor such as being conscientious, working hard, being punctual or controlling one’s impulses?

In other words, there need not be a direct causal link between religious faith and health and longevity.

About a dozen studies have shown that religious people tend to share other personality traits, although it is not clear whether these arise from genetic or environmental factors. These include the ability to get along well with others and being conscientious, working hard, being punctual, and controlling one’s impulses.

Much of the earlier literature has been summarized in William Wright’s book “Born That Way.” I am particularly impressed with this area as it is in accord with the Prescribed Evolutionary Hypothesis and a deterministic view of the universe which I feel the facts, especially those concerning organic evolution, strongly indicate.

Albert Einstein put it this way:

“Our actions should be based on the ever-present awareness that human beings, in their thinking, feeling, and acting are not free but are just as causally bound as the stars in their motion.” Statement to The Spinoza Society of America, September 22, 1932

and

“ Everything is determined… by forces over which we have no control. It is determined for the insect as well as for the star. Human beings, vegetables or cosmic dust - we all dance to a mysterious tune, intoned in the distance by a mysterious piper.” In the Saturday Evening Post, October 26, 1929.

Just thoughts, but thoughts that give me pleasure.

John A. Davison

steve

My thought experiment question is, would fundamentalists support abortion when the fetus had that gene situation?

To paraphrase the great Bill Clinton: If they did, they wouldn’t tell you! ;)

But consider this: if atheists tried to pass a law prohibiting the abortion of fetuses carrying that gene, would fundamentalists argue that such a law is unconstitutional and try to prevent that law from being passed?

Check out here for a quick and dirty definition of heritability. Reed is saying that heritable means that a trait is “inherited,” but heritability is the measure of the proportion of phenotypic variation in a population attributable to genetic variation. In this example, religiousness is the phenotype. If there is no genetic variation in a population, then a trait has heritability=0, even though some aspect of the phenotype (or even the entire phenotype) is determined by genetics. That is why the heritability of a particular trait is only relevent within the population it was determined. I’ll repeat again, it is not a very useful metric (of course not as useless as mean fitness).

I would like to know what her defintion of religiousness was? From the “new Sceintist” article it was just checking how often children who were raised in religious families continued to follow those traditions.

From what I read…the amount of change in behavior was more or less the same in twins.

My question: Is this “heretiable train” limited only to religious behavior? Could it also apply to other behaviors taught in child hood?

We may not have found a “religious” gene but maybe a “listen to your mother” gene? :)

Is this what its come to? Genes associated with thoughts and beliefs? Can we expect conservative and liberal genes? Classical and jazz genes? Impressionist and realist genes? This is absurd.

Depression is linked to thoughts of suicide. Are you saying it’s absurd to think that a gene could be associated with depression?

This suggests a new strategy for defeating Creationism: Start a human breeding program.

A gene could be associated with depression because it may cause a decrease in a certain hormone that would make the individual depressed. However, how could a gene be associated with religiousness? The idea seems rediculous. What’s next? Genes for determining whether a person believes that there is life in outer space?

Religiousness very well may be based on hormones or have some other chemical basis in the brain. We’re talking about feelings of conviction and the occasional state of bliss, not academic notions such as whether there’s life in space.

Hasn’t Dawkins suggested that, since humans are relatively slow to mature and require parental assistance for an extended period of time, the tendency to take arbitrary statements “on faith” in early childhood is a survival characteristic? Not being equipped with much in the line of instinct, it behooves infants and very young children to behave (as Patrick Harris said, “listen to your mother”) willy nilly and hope for the best.

Now, what if much of what is imparted at this age goes beyond health and safety directives, and includes, uh, highly speculative material presented as flat take-it-or-leave-it fact? What if this in a position to impart this information know this, and do so for that very reason?

Now, why would identical twins (all else being equal!) tend to diverge less from such early instruction than fraternal twins as they grew older? It seems possible that this tendency to stay alike is genetic, but alike “about religion” is a red herring, because they stay alike more across the board.

My comment merely showed that associating genes with thoughts is not in principle absurd. Whether there’s a link between x gene and y belief is a different question.

Jeff Low: don’t forget the closely related research on degree of handedness and affinity for creationism …

http://www.pandasthumb.org/pt-archi[…].html#c17195

Title: Handedness and Religious Beliefs Authors: Douglas Degelman, Denee Heinrichs, and Hisashi Ishitobi Affiliation: Vanguard University of Southern California

Introduction: Niebauer, Christman, Reid, & Garvey (in press) have found that strongly-handed individuals, whose two cerebral hemispheres may interact less than mixed-handed individuals, were more likely than mixed-handed individuals to believe in Biblical creationist accounts of human origins. Niebauer et al. argue that the two hemispheres are involved differently in how individuals maintain and update their beliefs, with the left hemisphere more involved in maintaining consistency of beliefs and the right hemisphere more involved in monitoring beliefs and registering inconsistencies. If interhemispheric communication underlies the updating of beliefs, and if strongly-handed individuals evidence less interhemispheric interaction than mixed-handed individuals, then strongly-handed individuals may be more likely than mixed-handed individuals to maintain religious beliefs that have been uncritically held.

Conservative and liberal genes were anticipated by Gilbert and Sullivan before the dawn of the 20th century:

“Every boy and every girl that is born into the world alive, Is either a little liberal or a little conservative.” Iolanthe

Liberal versus conservative biases have already been demonstrated to have a genetic basis. I recommend William Wright’s book “Born That Way.”

That is why I am so taken with Ann Coulter. We both see the world the same way. It is in general accord with the the Prescribed Evolutionary Hypothesis that everything, and I mean everything, is genetic. Don’t blame me. That is the way it is. Get used to it, that is if your genes will allow it.

John A. Davison

In my not even slightly humble opinion, religion is one of the primary reasons that we are the only remaining large primate species within our genus, and unquestionably the dominant organism in our size range.

One of the benefits religion conveys is the ability to transmit complex information intact across many generations. If an apparently irrational “don’t eat those – they are unclean” holy prohibition only prevents one massive red tide shellfish poisoning episode every five generations, it has proved its worth.

Another advantage is indirect: because of the nonlocal social cohesion that religion promotes, there is no practical upper limit to the size of a human war party. Such was apparently not the case with any of our late competitors.

Just ask anybody in the Balkans about the role of religion in establishing group identity.

Ok. So, this is kind of like when I’m gambling and I don’t know what the next card, then the feeling I get of what it might be is encoded in my genes? How so?

Title: Handedness and Religious Beliefs Authors: Douglas Degelman, Denee Heinrichs, and Hisashi Ishitobi Affiliation: Vanguard University of Southern California

Introduction: Niebauer, Christman, Reid, & Garvey (in press) have found that strongly-handed individuals, whose two cerebral hemispheres may interact less than mixed-handed individuals, were more likely than mixed-handed individuals to believe in Biblical creationist accounts of human origins. Niebauer et al. argue that the two hemispheres are involved differently in how individuals maintain and update their beliefs, with the left hemisphere more involved in maintaining consistency of beliefs and the right hemisphere more involved in monitoring beliefs and registering inconsistencies. If interhemispheric communication underlies the updating of beliefs, and if strongly-handed individuals evidence less interhemispheric interaction than mixed-handed individuals, then strongly-handed individuals may be more likely than mixed-handed individuals to maintain religious beliefs that have been uncritically held.

So, in other words, we can’t think on our own. I’m 100% certain that living organisms were designed. Anybody care to show the genes that caused me to come to that conclusion?

This looks like a dead thread, but if anyone is interested in this…

steve Wrote:

Also, I wonder if the plaintifs in Dover will find a way to get the Wedge Document into evidence. Judges are smart people. The number one Intelligent Design quackhouse accidently releasing an internal document explaining that the long-term strategy with ID is to promote Jesus, should seal the deal on the legality of Creationism II.

I believe there are a few quotes from and mentions of the wedge document in the ACLU briefs that have been filed in this case.

text of ACLU complaint brief

About this Entry

This page contains a single entry by PvM published on March 17, 2005 5:11 PM.

When the Moon is in the 7th House… was the previous entry in this blog.

Evolution of the X chromosome is the next entry in this blog.

Find recent content on the main index or look in the archives to find all content.

Categories

Archives

Author Archives

Powered by Movable Type 4.361

Site Meter