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from "Born that way" theory
Is There a "Gay Gene"?
Many laymen now believe that homosexuality is part of
who a person really is from the moment of conception.
The "genetic and unchangeable" theory has been actively promoted
by gay activists and the popular media. Is homosexuality really
an inborn and normal variant of human nature?
No. There is no evidence that shows that homosexuality is simply "genetic."
And none of the research claims there
is. Only the press and certain researchers do, when speaking in sound bites to the public.
How The Public Was Misled
In July of 1993, the prestigious research journal
Science published a study by Dean Hamer which claims that there might be
a gene for homosexuality. Research seemed to be on the verge of
proving that homosexuality is innate, genetic and
therefore unchangeablea normal variant of human nature.
Soon afterward, National Public Radio trumpeted those findings.
Newsweek ran the cover story, "Gay Gene?" The Wall Street
Journal announced, "Research Points Toward a Gay Gene...Normal Variation."
Of course, certain necessary qualifiers were added within
those news stories. But only an expert knew what those qualifiers meant.
The vast majority of readers were urged to believe that
homosexuals had been proven to be "born that way."
In order to grasp what is really going on, one needs to
understand some littleknown facts about behavioral genetics.
Gene Linkage Studies
Dean Hamer and his colleagues had performed a common type of
behavioral genetics investigation called the "linkage study."
Researchers identify a behavioral trait that runs in a family, and then:
a) look for a chromosomal variant in the genetic material
of that family, and
b) determine whether that variant is more frequent in
family members who share the particular trait.
To the layman, the "correlation" of a genetic structure with a
behavioral trait means that trait "is genetic"-in other words,
inherited.
In fact, it means absolutely nothing of the sort, and it should
be emphasized that there is virtually no human trait without
innumerable such correlations.
Scientists Know the Truth about "Gay Gene" Research
But before we consider the specifics, here is what serious
scientists think about recent genetics-of-behavior research. From
Science, 1994:
Time and time again, scientists have claimed that
particular genes or chromosomal regions are associated
with behavioral traits, only to withdraw their findings
when they were not replicated. "Unfortunately," says
Yale's [Dr. Joel] Gelernter, "it's hard to come up with
many" findings linking specific genes to complex human
behaviors that have been replicated. "...All were
announced with great fanfare; all were greeted unskeptically in
the popular press; all are now in disrepute."{1}
Homosexual Twin Studies
Two American activists recently published studies showing that if
one of a pair of identical twins is homosexual, the other member of
the pair will be, too, in just under 50% of the cases. On this basis,
they claim that "homosexuality is genetic."
But two other genetic researchers--one heads one of the
largest genetics departments in the country, the other is at
Harvard--comment:
While the authors interpreted their findings as
evidence for a genetic basis for homosexuality, we think that
the data in fact provide strong evidence for the influence
of the environment.{2}
The author of the lead article on genes and behavior in a
special issue of Science speaks of the renewed scientific recognition
of the importance of environment. He notes the growing
understanding that:
... the interaction of genes and environment is much
more complicated than the simple "violence genes" and
intelligence genes" touted in the popular press.The same
data that show the effects of genes, also point to the
enormous influence of nongenetic factors.{3}
More Modest Claims to the Scientific Community
Researchers' public statements to the press are often grand
and far-reaching. But when answering the scientific community,
they speak much more cautiously.
"Gay gene" researcher Dean Hamer was asked by
Scientific American if homosexuality was rooted solely in biology. He replied:
"Absolutely not. From twin studies, we already know that half
or more of the variability in sexual orientation is
not inherited. Our studies try to pinpoint the genetic factors...not negate
the psychosocial factors."{4}
But in qualifying their findings, researchers often use
language that will surely evade general understanding making
statements that will continue to be avoided by the popular press, such as:
...the question of the appropriate significance level
to apply to a nonMendelian trait such as sexual
orientation is problematic.{5}
Sounds too complex to bother translating? This is actually a
very important statement. In layman's terms, this means:
It is not possible to know what the findings
mean--if anything--since sexual orientation cannot possibly be
inherited in the direct way eyecolor is.
Thus, to their fellow scientists, the researchers have been
honestly acknowledging the limitations of their research.
However, the media doesn't understand that
message. Columnist Ann Landers, for example, tells her readers that "homosexuals are born,
not made." The media offers partial truths because the scientific
reality is simply too unexciting to make the evening news; too
complex for mass consumption; and furthermore, not fully and
accurately understood by reporters.
Accurate Reporting Will Never Come in "Sound Bites"
There are no "lite," soundbite versions of behavioral genetics
that are not fundamentally in error in one way or another.
Nonetheless, if one grasps at least some of the basics, in
simple form, it will be possible to see exactly why the current
research into homosexuality means so littleand will continue to
mean little, even should the quality of the research methods
improveso long as it remains driven by political, rather than scientific
objectives.
Understanding the Theory
There are only two major principles that need to be carefully
understood in order to see through the distortions of the recent
research. They are as follows:
1. Heritable does not mean
inherited.
2. Genetics research which is truly meaningful will
identify, and then focus on, only traits that
are directly inherited.
Almost every human characteristic is in significant measure
heritable. But few human behavioral traits are directly
inherited, in the manner of height, for example, or eye color.
Inherited means "directly determined by genes," with little or no way of
preventing or modifying the trait through a change in the environment.
How to "Prove" That Basketball-Players are Born that Way
Suppose you are motivated to demonstratefor political
reasons--that there is a basketball gene that
makes people grow up to be basketball players. You would use the same methods that have
been used with homosexuality: (1) twin studies; (2) brain
dissections; (3) gene "linkage" studies.
The basic idea in twin studies is to show that the more
genetically similar two people are, the more likely it is that they will
share the trait you are studying.
So you identify groups of twins in which at least one
is a basketball player. You will probably find that if one identical twin
is a basketball player, his twin brother is statistically more
likely be one, too. You would need to create groups of different kinds
of pairs to make further comparisons--one set of identical twin
pairs, one set of nonidentical twin pairs, one set of sibling pairs, etc.
Using the "concordance rate" (the percentage of pairs in which
both twins are basketball players, or both
are not), you would calculate a "heritability" rate. The concordance rate would be quite
high--just as in the concordance rate for homosexuality.
Then, you announce to the reporter from Sports
Illustrated: "Our research demonstrates that basketball playing is strongly
heritable." (And you would be right. It would be
"heritable"--but not directly inherited. Few readers would be aware of the
distinction, however.)
Soon after, the article appears. It says:
"...New research shows that basketball playing is
probably inherited. Basketball players are apparently 'born that way!'
A number of outside researchers examined the work and found
it substantially accurate and wellperformed..."
But no one (other than the serious scientist)
notices the media's inaccurate reporting.
What All Neuroscientists Know: The Brain Changes with Use
Then you move on to conduct some brain research. As in the
well-known LeVay brain study which measured parts of the
hypothalamus, your colleagues perform a series of autopsies on the brains of
some dead people who, they have reason to believe, were basketball
players.
Next, they do the same with a group of dead nonbasketball players.
Your colleagues report that, on average, "Certain parts of
the brain long thought to be involved with basketball playing are
much larger in the group of basketball players."
A few national newspapers pick up on the story and
editorialize, "Clearly, basketball playing is not a
choice. Not only does basketball playing run in families, but even these people's
brains are different."
You, of course, as a scientist, are well aware that the
brain changes with use...indeed quite dramatically. Those parts
responsible for an activity get larger over time, and there are
specific parts of the brain that are more utilized in basketball playing.
Now, as a scientist, you will not lie
about this fact, if asked (since you will not be), but neither will you go out of your way
to offer the truth. The truth, after all, would put an end to
the worldwide media blitz accompanying the announcement of your
findings.
Gene Linkage Studies:
"Associated With" Does Not Mean "Caused By"
Now, for the last phase, you find a small number of families
of basketball players and compare them to some families
of nonplayers. You have a hunch that of the innumerable genes
likely to be associated with basketball playing (those for
height, athleticism, and quick reflexes, for example), some will be
located on the x-chromosome.
You won't say these genes cause basketball playing because such
a claim would be scientifically insupportable, but the public
thinks "caused by" and "associated with" are synonymous.
After a few false starts, sure enough, you find what you are
looking for: among the basketball-playing families, one
particular cluster of genes is found more commonly.
With a Little Help from the Media
Now, it happens that you have some sympathizers at
National People's Radio, and they were long ago quietly informed of
your research. They want people to come around to certain beliefs, too.
So, as soon as your work hits the press, they are on the air:
"Researchers are hot on the trail of the Basketball
Gene. In an article to be published tomorrow in
Sports Science..."
Commentators pontificate about the enormous public-policy
implications of this superb piece of science. Two weeks later, there
it is again, on the cover of the major national newsweekly:
"Basketball Gene?"
Now what is wrong with this scenario? It is simple: of
course basketball playing is associated with certain genes; of course
it is heritable. But it is those intermediate
physiological traitsmuscle strength, speed, agility, reflex speed,
height, etc.-which are themselves directly
inherited. Those are the traits that make it likely one will be
able to, and will want to, play basketball.
In the case of homosexuality, the inherited traits that are
more common among male homosexuals might include a greater than
average tendency to anxiety, shyness, sensitivity, intelligence, and
aesthetic abilities. But this is speculation. To date,
researchers have not yet sought to identify these factors with
scientific rigor.
What the majority of respected scientists now believe is that
homosexuality is attributable to a combination of
psychological, social, and biological
factors.
From the American Psychological Association
"[M]any scientists share the view that sexual orientation
is shaped for most people at an early age through complex
interactions of biological, psychological and social factors."{6}
From "Gay Brain" Researcher Simon LeVay
"At this point, the most widely held opinion [on causation
of homosexuality] is that multiple factors play a role."{7}
From Dennis McFadden, University of Texas neuroscientist:
"Any human behavior is going to be the result of
complex intermingling of genetics and
environment. It would be astonishing if it were not true for homosexuality."{8}
From Sociologist Steven Goldberg
"I know of no one in the field who argues that
homosexuality can be explained without reference to environmental
factors."{9}
As we have seen, there is no evidence that homosexuality is
simply "genetic"--and none of the research itself claims there
is.
Only the press and certain researchers do, when speaking in
sound bites to the public.
Endnotes
{1} Mann, C. Genes and behavior.
Science 264:1687 (1994).
{2} Billings, P. and Beckwith, J. Technology
Review, July, 1993. p. 60.
{3} Mann, C. op. cit. pp. 1686-1689.
{4} "New Evidence of a 'Gay Gene'," by Anastasia Toufexis, Time,
November 13, 1995, vol. 146, Issue 20, p. 95.
{5} Hamer, D. H., et al. Response to Risch, N., et
al., "Male Sexual Orientation and Genetic Evidence,"
Science 262 (1993), pp. 2063-65.
{6} The American Psychological Association's pamphlet,
"Answers to Your Questions About Sexual Orientation and
Homosexuality."
{7} LeVay, Simon (1996). Queer Science, MIT Press.
{8} "Scientists Challenge Notion that Homosexuality's a
Matter of Choice," The Charlotte
Observer, August 9, 1998.
{9} Goldberg, Steven (1994). When Wish Replaces Thought:
Why So Much of What You Believe is False. Buffalo, New York:
Prometheus Books.
The above article was adapted from two sources: a paper
entitled, "The Gay Gene?" by Jeffrey Satinover, M.D., in The Journal of
Human Sexuality, 1996, available by calling (972) 713-7130; and past
issues of the National Association of Research and Therapy of
Homosexuality (NARTH) Bulletin. For an in-depth discussion of
homosexuality and genetics, consult Dr. Satinover's 1996 book,
Homosexuality and the Politics of Truth, published by Hamewith/Baker Books.
Updated: 8 February 2008
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