No one is born gay
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It is reasonable to assume that
sexual behavior--in any and all of its manifestation—is directed by the
activity of many, possibly hundred of genes. But the exact and specific type of
sexual expression is also influenced by countless environmental forces that
interact with the genes in complex ways (Hubbard, 1997; Ridley, 2003).
Except for the rare physical
abnormalities (such as Huntington’s Disease) at the present time, there is no
evidence of a direct causative link between a single gene and complex psycho-social
behavior such as sexual preference (Collins, 2006). This is not my opinion but
read any book on behavior genetics or molecular biology and the authors will
unanimously agree that, at present, there is no gay gene.
Lewontin et al. stated this explicitly:
“Up to the present time no one
has ever been able to relate any aspect of human social behavior to any particular gene or set of
genes, and no one has ever suggested an experimental plan for doing so. Thus,
all statements about the genetic
basis of human social traits are necessarily purely speculative, no matter how positive they seem to be” (p.
251).
Dr. Francis S. Collins (MD and
PhD) head of The Human Genome Project has said:
There is an inescapable
component of heritability to many human behavioral traits. For virtually none
of them is heredity ever close to predictive…An area of particularly strong
public interest is the genetic basis of homosexuality. Evidence [indicates]
that sexual orientation is genetically influenced but not hardwired by DNA, and
that whatever genes are involved represent predispositions, not
predeterminations. (2006).
Stein (1999), a psychologist
explains:
Genes in themselves cannot
directly specify any behavior or psychological phenomenon. Instead,genes direct
a particular pattern of RNA synthesis, which in turn may influence the
development of psychological dispositions and the expression of behaviors.
There are many intervening pathways between a gene and a disposition or a
behavior, and even more intervening variables between a gene and a pattern that
involves both thinking and behaviors…No one has presented evidence in support
of such a simple and direct link between genes and sexual orientation.
Baker (2004) a behavioral psychologist
agrees:
Most physical traits and
conditions such as height, blood pressure, weight and digestive activity stem
from many genes that vary in activity depending on environmental contexts. The
same is true of all complex [psycho-social] behaviors. Each is affected by
multiple genes interacting with multiple environmental
influences…Unfortunately; many people have a different impression. They think
that a gene controls a behavioral trait. This is genetic determinism, the
belief that the development of an organism is determined solely by genetic
factors. Genetic determinism is a false belief. It comes from misunderstandings
of scientific research…The fact is that so far,
scientific research has not
confirmed any one-to-one correspondence between a gene and a [complex] human
behavior. Behavior results from the activity of multiple genes amidst the
influence of multiple environmental factors (p. 17-18).
Two scientists, McInerney and
Rothstein, who
have worked on the Human Genome Project, caution us when interpreting research
on genetic “causes” of behavior:
How do genes influence
behavior? No single gene determines a particular behavior. Behaviors are
complex traits involving multiple genes that are affected by a variety of other
factors. This fact often gets overlooked in the media report hyping scientific
breakthroughs on gene function, and unfortunately, this can be very misleading
to the public” (2007).
Evolutionary anthropologist
Sarah Blaffer Hardy adds:
Nature cannot be
compartmentalized from nurture, yet something about human imaginations
predisposed us to dichotomize the world that way…Complex behaviors like
nurturing, especially when tied to even more complex emotions like “love,” are
never either genetically predetermined or environmentally produced” (from
Hrdy’s 2000 book “Mother Nature”, cited in Ridley, 2003, p. 246).
Matt Ridley (2003) concurs:
Genes are enablers, not
constrainers. They create new possibilities for the organism; they do not
reduce its options…The new possibilities are open to experience, not scripted
in advance. Genes no more constrain human nature than extra programs constrain
a computer…Genes, unlike gods, are conditional. They are exquisitely good at
simple if-then logic: if in a certain environment, then develop in a certain
way…Don’t be frightened of genes. They are not gods, they are cogs” (Ridley, p.
250).
In summary, there is no
undisputed evidence that same-sex behavior is hard-wired in the brain. Genes
are
complex strands of DNA that
through the processes of transcription and translation, direct the synthesis of
amino acids into larger
proteins that influence cell structure and functioning (How Genes Work, 2007;
Schwartz & Azar, 1981).
Complex social activities such
as sexual behavior cannot be directly traced to the activity of a single gene
(Parens, Chapman & Press, 2006; Peele, 1995; Rutter, 2006). Many uninformed
people take a simplistic view of behavioral genetics: they believe that one
gene controls and determines a specific behavior. This is true for a very few,
abnormal physical conditions including Huntington’s disease, cystic fibrosis,
PKU, and achondroplasia (Dwarfism). This fact has led some to believe that
there is an alcoholic gene, a manic-depression gene, or a gay gene. However,
“Genes do not act as master puppeteers within us.
They are chemical structures
that control the production of proteins; thereby indirectly affecting
behavior…Genes do not determine one’s destiny” (Plomin et al., 1990, p.13). “It
is an oversimplification to say that any gene is ‘the gene for a trait’. Each
gene simply specifies one of the proteins involved in the process [of
gene-environmental interaction], notes Hubbard (Hubbard & Wald, 1999, p.
44).
Complex psycho-social behaviors
such as sexual preference are not determined by a single gene, but by a
gene-environmental process
involving possibly hundreds of genes acting through complex environmental
factors (Rutter, 2006). “The
fact is that so far, scientific research has not confirmed any one-to-one
correspondence between a gene and a [complex psycho-social] behavior. Behavior
results from the activity of multiple genes amidst the influence of multiple
environmental factors” (Baker, 204, p. 18).
If you are still unconvinced
that scientists have not found the “gay gene,” let me share with you one final
bit of knowledge about behavioral genetics. Suppose you could isolate a segment
of DNA that you thought was related to homosexuality. You could then specify
the exact, let’s say 183,000 base pairs, that make up this portion of DNA.
The “gene” would look something
like this sequence: TA, GC, TA, TA, GC, CG, AT, AT, AT, GC, GC, CG, TA….. The
letter A, T, G, and C stand for the four nucleotides that make up DNA: adenine,
thymine, guanine, and cytosine. Now you get DNA samples of other gay men and
examine this exact 183,000 base-pair sequence on the same chromosome. You
compare the sequencing of TA, CG, GC, and AT along the whole length of the gay
gene. Surprise: The sequences from 10 gay men don’t nearly match! Some portions
are similar, but most are dissimilar.
But you don’t give up. You
recruit the brothers of the original 10 gay men. You code their nucleotides at
the same foci on the suspected gay gene. You find that the DNA sequences of the
gay/non-gay brothers are more similar than that of the gay/gay men. In other
words, the non-gay brothers’ DNA sequence is more similar to their gay brothers
than is the sequencing of the gay men to each other! You are persistent so try
once more.
You recruit another 20 gay men
and code their DNA. Again, you find that there is more dissimilarity in the
sequences of base pairs between the gay men than similarities. Undaunted, you
write another grant and keep looking. Scientists have actually done what I have
just described but with only few inherited diseases like emophilia (Lippman,
1991). Hubbard concluded that most scientists believe that “base sequences can
vary a great deal without any change being apparent in the corresponding trait”
(1999, p. 55; also see Gianelli, 1990). That’s an amazing fact and puts the
crimp in anyone’s plan to discover the elusive gay gene.
The genetic theory of
homosexuality rests on a foundation of three seminal studies in the early
1990’s--
which all have serious
methodological, sampling, and interpretation problems. Simon LeVay (1991)
dissected the brains of 19 gay men and supposedly 16 non-gay men and found, on
average, a slighter smaller area of the hypothalamus (INAH-3) in the gay men.
He then “suggests that sexual orientation has a biological substrate.” There
were several major flaws with his research: (a) the sample was small, (b) the
control group was inappropriate, (c) there is no evidence that the INAH-3 part
of the brain had anything to do with sexual preference, (d) AIDS could have
caused the brain differences, and (e) the study has never been replicated.
Michael Bailey and Richard
Pillard (1991) concluded there must be a genetic cause to homosexuality because
they found higher rates of homosexuality among identical than fraternal twins
and even less concordance (similarity) among adopted siblings. These
quantitative genetic studies have similar limitations.
- First, the samples may be biased because
researchers usually recruit a volunteer sample from gay publications and
organizations.
- Second, such studies require a large sample in
order to make valid heritability estimates, and samples are usually small.
- Third, environmental factors are usually not
studied so its effects are
unaccounted for.
- Forth, there are obvious interpretation problems
because only about half of identical twins reared in the same family have
a gay brother. If genes determined homosexuality then both brothers should
be gay.
- Fifth, other twin studies have not supported
their claim of a strong genetic component to homosexuality (see
Hershberger, 1997). Dean Hamer and his colleagues (1993) examined a small
section of the X chromosome in the families of 40 gay men. In a
complicated pedigree analysis, Hamer claims that homosexuality is
transmitted through
- the maternal side and is genetically linked to
the X chromosome region known as Xq28. His conclusion has been criticized
by several authors (Baron, 1993). If homosexuality were a simple Mendelian
trait (like eye color) then Hamer should have found a higher incidence of
homosexuality among brothers. There is no evidence that the Xq28 section
of the chromosome has anything to do with sexual behavior!
Hamer did not assess this
genetic marker on the heterosexual men in the sample to see if they possessed
it also. Rice, Anderson, Risch and Ebers (1999) did a similar but larger study
(N=52) and found no support for an X-linked gene underlying male homosexuality.
Hamer’s study has never been replicated. Thus, none of these studies proves a
direct causation between a gene and the complex psychosocial behavior of sexual
preference (Dailey, 2003; Lasco, Jordan, Edgar, Petito & Byne, 2002). The
more amazing point is that all of these men (LeVay, Bailey, and Hamer) readily
admit they there research does not prove there is a gay gene and that
environment is a major factor in homosexuality!
Even if biogenic factors have a
weak, but indirect, affect on sexual orientation on some individuals,
Valenstein (1998) explains:
Most recent claims that a gene has been
discovered that causes alcoholism, schizophrenia, [or] homosexuality…have proven
illusory… genes do not produce behavioral or mental states. Genes carry the
instructions and template for producing and assembling amino acids and proteins
into anatomical structures. Behavior and mental traits; however, are the
product of an interaction between anatomical structure and experience…Even
where there is compelling evidence that some behavioral or mental trait is
influenced by genetic factors it is almost always a predisposition, not a
certainty… a predisposition is not a cause. (p.140-141, 224).
Even advocates for a genetic
explanation of homosexuality such as Szuchman (2002), concluded that the
scientific evidence for a
biological cause of homosexual behavior is “remarkably flawed, such that no
unbiased view for or against many of these factors [i.e., biogenetic causes] is
possible…We still have no good evidence of biological influences on sexual
preference or sexual orientation” (p. 212). Gay advocates Parker and DeCecco
(1995) conceded that “research into possible biological bases of sexual
preference has failed to produce any conclusive evidence” (p. 427).
Genes or hormones may make it
more likely that a person will display certain temperament characteristics or
atypical gender role behaviors. These outcomes may make the child more vulnerable
to child trauma (e.g., sexual abuse, negative fathering, and rejection by
same-sex peers). The child’s psycho-social sequelae may, in turn, set up
conditions where the child is more likely to consider the homosexual option
(Stein, 1999).
Bancroft (1990) has stated that
biological factors that may influence sexual orientation “need to be understood
as interacting with the effects of social and cognitive learning rather than
having direct effects of their own” (p. 109). Thus, genetic factor may indirectly
influence sexual orientation, but there is no evidence of a direct casual link
between a gay gene and homosexual behavior.
You may like the analogy of
gene-environment interaction provided by Robert Plomin et al. (1980):
A sailboat needs both sails
[environment] and a hull [genes]. The ‘behavior’ of a sailboat (speed, turning
ability and direction) depends on the design of its sails and the design of its
hull. The aerodynamic shape of the sails, their number and size, and their
positioning are important. The depth, width, length, and shape of the hull are
also important. Obviously, for sailboats, there can be no behavior without both
sails and hull, but this does not restrict us from asking about the independent
contributions of sail design and hull design to the behavior of
sailboats…Behavior requires both genes and environment (p. 359).
Yet, even this example is
flawed. The missing factor in Plomin’s analogy is the “captain” at the helm of
the ship. That captain is “agency,” “free will” and “choice”! Regardless of
sails (environmental factors) and hull design (genetic predispositions), the
captain can make moral decisions independent of both sails and hull. The
captain may be constrained by genes and environment—but he is not absolutely
determined by them. Agency intervenes, on many occasions, at various times and
places, in the interplay between genes and environment.
The British poet William Ernest Henley (1849-1903), in his famous poem
“Invictus” (Latin for unconquerable) penned this famous line:
“It matters not how strait the
gate, how charged with punishment the scroll. I am the master of my fate: I am
the captain of my soul.”
There is clear evidence that
many men and women are at the helm controlling their sexual behavior and making
choices regarding sexual preference. I believe that the hypothetical evidence
for genetic determinism of homosexuality is overstated and overrated. Most
people do not have the knowledge to understand the research and are simply
hoodwinked by the pro-gay activists.
It is obvious to me, and to
many others, that environmental factors play the major role in same-sex
behavior, if this were not so how does one explain the thousands of men and
women who have left homosexuality. Consider the recent example of Michael
Glatze, founder of Young Gay American Magazine, film producer, pro-gay
lecturer and author, and well-recognized leader in the gay movement. At age 14
he believed himself to be “gay,” but at age 30 he “seriously began to doubt”
what he was doing (Moore, 2007).
He explains:
Knowing no one who I could
approach with my questions and my doubts, I turned to God…It became clear to me
that homosexuality prevents us from finding our true selves…I was leading a
movement of sin and corruption…Now I know that homosexuality is lust and
pornography wrapped into one. I’ll never let anybody try to convince me
otherwise…Healing from the wounds caused by homosexuality is not easy—there’s
little support. In my experience, coming out from under the influence of the
homosexual mindset was the most liberating, beautiful and astonishing
things I’ve ever experienced…I
believe that all people, intrinsically know the truth. I believe that is why
Christianity scares people so much. It reminds them of their conscience, which
we all possess. Conscience tell us right from wrong and is a guide by which we
can grow and become stronger and freer human beings (in Moore, 2007, p.3-5).
In conclusion, I believe that
the genetic evidence for homosexuality is just not there. It’s the values and
politics of homosexuals and their supporters that is driving the gay gene
agenda, not good science.
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