Fagan I
Homosexuality: Nature, Nurture, or Politically Correct?
The question of the nature of homosexuality has become an issue of a
significantly political, as well as, politically correct nature. Is it nature or nurture? The
fact that the standard question has eliminated the psychological possibility is a politically
correct success. The motivational politics of homosexuality are clarified by reading
"Homosexual Conduct and the Law," by Irving J. Sloan:
The earliest legal argument for outlawing homosexuality is found in
Plato's Laws ... Prohibitions on male homosexuality in the Old Testament,
"Thou shalt not lie with mankind, as with womankind: it is an
abomination (Leviticus: 18:22). . . ." "If a man also lie with mankind, as
with a woman, both of them have committed an abomination: they shall
surely be put to death; their blood shall be them (Leviticus: 20:13)."(1)
To paraphrase Sloan, death by burning, hanging, burying alive... exile, castration,
corporal punishment, etc., have been politically correct solutions for homosexuality (2 4).
This history presents some of the motivational forces driving advocacy groups to promote
studies indicating a genetic link to homosexuality. Recent genetic studies have shown
links to personality (Colt, George Howe, 1998), overall happiness, psychornotor reaction
time (Simonen et al, 1998), mathematics disability (Alarcon, Marciela, 1997) and many
factors which had been presumed to be the province of nurture (environment). Is there a
genetic component to homosexuality as opposed to heterosexuality? This question begs
for answers, and answers are available if one approaches the subject matter logically.
In this age of computers, the logical starting place is established databases, and in
this specific case, a database of twins would be ideal. Hershberger's study of the study
by Lykken et al., "The Minnesota Twin Family Regist is exactly that and is used
extensively by many of the authors whose works are cited on these pages. To paraphrase
the study, twins registered in the State of Minnesota from 1936 to 1955 were sent
questionnaires, the replies allowing analysis of whether or not the twins were
monozygotic (identical) or dizygotic (fraternal). The questionnaire also requested the
twin~ sexual orientation, his/her twil sexual orientation, his/her non twin siblings sexual
orientation, marital status, sexual orientation before age 25 and after age 25, and the
number and frequency of sexual encounters with persons of the same or opposite sex (3
of 3, 5,6,7 of 7).
An initial study of the Australian Twin Registry database by Michael Bailey of
Northwestern and Richard Pillard of the Boston School of Medicine was highly
publicized internationally as the proof of a high genetic influence for
homosexualit A(Shapiro 4 of 6),,The study was refuted by one of the authors in a
subsequent and much less publicized study, as documented by Jones in "The Incredibly
Shrinking Gay Gene ... .. Michael Bailey of Northwestern has produced a study that
refutes his earlier research conducted with Richard Pillard of the Boston School of
Medicine, which claimed that there is a high genetic influence on homosexuality "(53).
In this same study " Only 3 pairs of identical male twins were both homosexual out of a
total of 27 male identical twin pairs where at least one twin was homosexual"(53). These
27 pairs had 100% gene match in the individual twin pairs. If the gene was a significant
influencing factor, the incidence of homosexuality for both twins should have been much
higher. This is saying that homosexuality is not a genetic marker. These are identical
twins with same color eyes (genetic marker), same hair color (genetic marker), near
100% shared attributes (genetic markers), but no genetic marker for homosexuality.
Actually, 10% of the pairs were both gays, which begs a question.
Did the twin participant questionnaires used in the study ask if the twins were
raised by one or more gay parent/s? This is significant because children of gay parents
are 10 times (30%) as likely to be gay as the general population (3%)(Cameron, 1997, 8
and 9 of 14). In a twin study this is significant because it could cause sample bias. If this
error is not eliminated from any twin stud an implication of genetic causation for
homosexuality will result; however, it will be a very small implication statistically. For
example, relate to the 27 pairs of twins and if one parent was gay (I in 33, or 3% would
be the average), then it is a strong possibility that one of the homosexual pairs could have
been caused by that factor and it dilutes an already minimal percentage (10%) to a lower
percentage (7.4%). It is worth noting again that this genetic marker is the same marker
that causes the 100% match of hair color and many other attributes that motivate the
researcher to choose a monozygotic twin study for meaningful analysis.
In a Minnesota Twin Registry study, "A Twin Registry Study of Male and Female
Sexual Orientation" by Hershberger, this data is analyzed with particular emphasis on the
monozygotic twins, because this represents an identical gene match (100%). This is
important for the purpose of the study because it would indicate that the sexuality of the
one twin has to be exactly the same for the co twin if genetics causes the sexual
orientation. As in the Australian study, this is not the case, as this quote from the
Hershberger study reveals.
For men, depending on the criterion used, the prevalence of homosexuality
ranges for 1.06% to 3.24%, with an average of 2.49%; for women, the
range is from.55% to 2.11%, with an average of 1.68%. If combined with
bisexuality, the average rises to 4.57% for men and 3.26% for women.
These rates of homosexuality are very similar to those found in studies
using probability samples conducted in the United States and elsewhere(4
of 9 in 2 of 3).
The Hershberger study also states; "Specifically, significant genetic effects were
found for self identified female homosexuality, but not for male homosexuality, in both
the twin and extended family analyses."(5 of 9 in 2 of 3) The questionnaire used for this
study is included (6 of 7 and 7 of 7 in 3 of 3), and the question of gay parents is not
included, causing the same potential flaws as indicated for the Australian study.
In the case of monozygotic twins, any marker that does not match is the deviation.
The deviation should be measured against 100%, meaning the further away from 100%
(which is the expected match), the greater the proof that the factor is not genetic. If twins
do not have the same eye color, they are not monozygotic, meaning no 100% gene match.
Does this statement sufficiently dramatize genetic correlation?
The factual conclusions do not support a link between genetics and
homosexuality. Many institutions have attempted to stand on high moral ground by
giving generous interpretations of minimal statistical data implying genetic
homosexuality. The data should be overwhelming, if true, in a monozygotic twin study,
most certainly not a minimal statistic. The ABCNEWS.com special, "Nurture, Not
Nature" concludes that a sense of humor is not genetic (1). Overall happiness: however,
is genetic as acknowledged by Simonen et al (1998). Asa reminder, referring to Emma
Wilson's, "Textuality and (homo) Sexuality in Tournier's Les Meteores" to acknowledge
the psychological inferences, in this case, narcissism, regarding homosexuality might be
enlightening (9 of 9). The backlash caused by the historical overreaction to
homosexuality is analogous to affirmative action. Do the words, "too much of a good
thing," strike a responsive chord here?
Works Cited
Alarcon, Maricela, DeFnries, J. C, and Light, Jacquelyn Gillis. "A Twin Study of
'e i
Mathematics %Disabill urnal ofLearning Disabilities. Nov/Dec 1997. 617
23.
Cameron, Paul, and Cameron, Kirk. "Did the APA Misre2en the S*,,, ntific Literature
to Courts in Support of Homosexual Custo e Journal of Psy&logy May
1997. 313 32.
Cameron, Paul, and Cameron, Kirk. "Homosexual Parents". Adolescence. Winter 1996.
757 76.
Colt, George Howe. "Were You Born That Way?". Life. April 1998. 38 42.
Hershberger, Scott L. "A Twin Registry Study of Male and Female Sexual Orientation".
The Journal of Sex Research. 1997. 212 22.
Jones, Stanton L. "The Incredibly Shrinking Gay Gene". Christianity Today. Oct. 1999.
53.
Shapiro, Joseph P. "Kids With Gay Parents". U.S. News & World Report. Sept. 1996. 75
6.
Simonen, Riitta L, Videman, Tapio, and Battie, Michele C. "The Effect of Lifelong
Exercise On Psychomotor Reaction Time: a Study of 38 Pair of Male
Monozygotic Twins. Medicine and Science in Sports and Exercise. Sept. 1998.
1445 50.
Sloan, Irving J. "Homosexual Conduct and the Law". Ed. Irving J. Sloan. Oceana
Publications. London/Rome/New York. 1987.
Viegas, Jennifer. "Nature, Not Nurture". ABCNE WS. com. April 14, 2000.
Wilson, Emma. "Textuality and (homo)Sexuality in Tournier's Les Meteores". Romanic
Review. Jan. 1995. 115 27.