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Basic information on sexual orientation


Sexual orientation and behavior.
What causes sexual orientation:
Is it nature, nurture, a choice,
an addiction?
Can it be "cured?"
Morality of sexual activity.

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About sexual orientation and sexual behavior:

star Most of the public agree that three sexual orientations exist. They are defined by a person's feelings of attraction to:

  1. Only persons of the opposite sex. They have a heterosexual orientation and include about 90% of all adults; or

  2. Only persons of the same sex. They include about 5% of adults who have a homosexual orientation; or

  3. Persons of both genders. They include about 5% of adults who have a bisexual orientation. Most are not attracted to persons of both sex equally. This group, alone, can be said to usually have a "sexual preference."

Some regard asexuality -- lack of sexual attraction to other persons -- to be a fourth sexual orientation. But others criticize this belief, feeling that this concept is similar to not collecting stamps being a hobby.

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Cause of sexual orientation:

star There are four main opinions about the cause(s) of a person's sexual orientation:

  1. Many religious and social conservatives regard sexual orientation to be a choice that people make, perhaps in their teen years. Many feel that the cause cannot be genetic, because persons with a homosexual orientation tend to have fewer children. If homosexual orientation were purely caused by genetics, then they believe that the number of gays and lesbians would be reduced each generation and eventually die out. Yet homosexual orientation has existed for millennia.

    Others say that homosexual and bisexual orientation is caused by poor parenting, or sexual victimization as a child.

  2. Most religious liberals and professional mental health organizations believe that a person's sexual orientation is determined before birth by genes in a person's DNA and/or by epigentics. (The latter is a layer covering a persons DNA that turn individual genes on or off.)

    Researchers have not been notably successful at identifying a single "gay gene."

    The most definitive study to date was performed by a group of scientists in the UK, US, Netherlands, Australia, Sweden and Denmark. It involved about a half million participants of European ancestry. Their report was published in journal Science during 2019-AUG. 10

    They found that:

    - There is no single gay gene!

    - "Instead, thousands of genetic variations across the human genome contributed to overall sexual orientation."

    - Moreover, the study estimated genetics only accounted for between 8% and 25% in determining sexual preferences - not enough to predict a person's orientation. 11

    (Presumably, they use the term "sexual preferences" to refer to "sexual orientations.") They detected five genetic markers in human DNA that are associated with same-sex sexual behavior. Some work in the same way in both biological males and biological females. However, others work differently in the two biological genders. The five markers' influence overlaps with other markers for several other traits, like openness to experience and risk-taking behavior.

    - The patterns that they found were "based on statistical patterns in the data as a whole, and no conclusions can be drawn for any particular individual. It is thus not possible to predict or identify someone’s sexual behavior or sexual orientation from their DNA." 12

    However, a few years before this study, a remarkable development regarding epigenetics was developed. "Epigenetics" refers to a layer on top of a person's DNA that turns various genes on and off. A test was developed that analyzes a biological man's saliva and predicts with an accuracy of 83% whether he has a homosexual orientation.

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Interpretation of the cause(s) of sexual orientation:

Unfortunately, most conservative news sources zeroed in on the 2019 large scale study and emphasized that NO SINGLE GENE causes a person to have a homosexual orientation. They ignored the earlier epigenetic research findings. And so, for example, Mercatornet used the headline:

"What? I thought I was born gay!

A new study makes the case for special rights for LGBT folks a bit harder."

Unfortunately, they did not indicate what "special rights" the LGBT is continuing to seek. In some areas of the world, they have obtained equal rights to marry, and/or discrimination has been banned for everyone on the basis of their sexual orientation. But the author of this article is unaware of any "special rights" that they have sought or obtained.

Integrating the results of previous studies:

  • Combining the two studies on epigenetics and genetics, it appears that a person's DNA partly determined a person's sexual orientation, but that their epigenetics is the main determining factor. Both DNA and epigenetics are determined before birth and remain in place until their death.

  • Researchers have also determined that the female relatives of homosexuals tend to have more children for a reason that has not been determined. This would prevent the percentage of people with a homosexual orientation from declining in numbers from generation to generation and thus prevent homosexuality from dying out.

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Morality of sexual behavior:

star There are two main conflicting opinions about the morality of sexual behavior, assuming that precautions are in place to prevent STI infection being transmitted, and to prevent unwanted pregnancy:

  1. There is only one normal, natural, and moral sexual behavior. It involves sexual activity between one woman and one man who are married to each other. All other behaviors are immoral.

  2. All sexual behavior that is mutually agreeable between two adults or older teens is moral.

star Beliefs about sexual orientation and behavior profoundly affect what a person believes about:

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Accuracy of public opinion polls:

Unfortunately, public opinion polls are notoriously inaccurate on some topics. People being polled by a stranger over the telephone often don't tell the truth. Two examples are:
  • When polling agencies ask adults in the U.S. whether they have attended a religious service in the past week, they generally obtain an affirmative answer from about 40% of the subjects. But when church attendance is directly measured by counting people entering churches, temples, mosques, etc. the actual value is about 20%. Many people apparently believe that attending a church is a "good thing" and thus do not answer the question truthfully.

  • When polling agencies ask adults in the U.S. whether they are an Atheist, results range from 3% to 11%. Many people, including many Atheists themselves, believe that to be an Atheist is not "socially acceptable." However, a research group designed a public opinion poll that made an accurate estimate of the percentage of atheists without requiring the subject to admit directly that they were an Atheist. They found that about 26% of U.S. adults are actually Atheists. This implies that most Atheists are unwilling to admit their religious beliefs to polling agencies.

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More about sexual orientation: Is it chosen or genetic; fixed or changeable?:

Many religious and social conservatives believe that sexual orientation is chosen and can be changed with some effort. In contrast, many religious and social progressives, and those in the LGBT community, feel that a person is born with a sexual orientation because of something related to their genetic structure and is fixed. Further, their sexual orientation can be detected by child psychologists in pre-school children. Ned Flaherty posted a comment on the PolicyMic.com web site stating that:

"Sexual orientation has been proven to have at least 21 biological links, which can be observed in: twins, birth order, finger length ratio, fingerprint ridge density, Caucasian limb/hand-to-height ratio, hair pattern, handedness, hearing, vocal pitch, eye blinks, verbal fluency, spatial memory, amygdala activity, hypothalamus nucleus size, penis size, auditory/inner-ear function, suprachiasmatic nucleus size, stress, sweat, brain size symmetry, and X chromosome Xq28. Some of these links differ by race, thus further proving a biological basis." 1

Stanford University researchers Michal Kosinski and Yilun Wang, released a report in early 2018 documenting an Artificial Intelligence study in which over 30,000 portraits were uploaded from a dating web site and analyzed by computers in an attempt to identify which of the men and women had a homosexual orientation. Their computer programs correctly identified men who were gay 81% of the time and lesbian women 71%.

An article in cozzoo.com stated:

"The study proclaimed that biologically speaking, a gay man’s facial structure proved to be more effeminate and a lesbian’s more masculine. ... The Stanford researcher said:

'Gay faces tended to be gender atypical. Gay men had narrower jaws and longer noses. Lesbians had a larger jaw'." 7

This supports the:

"Prenatal Hormone theory of sexual Orientation. According to theory, one’s sexuality is determined before they are born, based on hormonal exposure in the womb.

Basically, characteristics like the faintness of beard and mustache in gay males is linked to the under exposure of male hormones like testosterone which could cause a feminizing effect, meaning less hair." 7

The article created a "media uproar" among LGBT groups who worried about the safety aspects of gays and lesbians who are keeping their sexual orientation secret becoming known in anti-gay communities. The chief digital officer at Glaad -- a main pro-LGBT group -- said that:

"... at a time where minority groups are being targeted, these reckless findings could serve as weapon to harm both heterosexuals who are inaccurately outed, as well as gay and lesbian people who are in situations where coming out is dangerous." 7

Gay marriage (a.k.a. same-sex marriage) -- and equal rights for the LGBT community generally -- have been among the most bitter and active religious conflicts in the U.S. Much of the conflict has been influenced by beliefs about the cause or causes of sexual orientation, and whether it can be changed later in life. With the passage of time, public support of gay marriage has risen steadily, from 28% in 1996, to about 50% in 2011. After the U.S. Supreme Court legalized same-sex marriages in mid-2015, acceptance of such marriages has increased more rapidly. The Gallup Poll found it had reached about 63% in 2017 8 and 67% in 2018. 9 This includes 83% of Democrats, 71% of Independents and 44% of Republicans. 9

Only 31% of adults are opposed. Only 2% had no opinion -- an unusually small percentage for such polls. More polling details.

As of 2018-OCT, Wikipedia reports that:

  • A majority of adults opposes gay marriage in only one state: Alabama.

  • Support for gay marriage has reached 80% in two states: Massachusetts and Vermont and in two urban areas: Boston, MA and Seattle, WA.

Exodus International was the leading evangelical Christian group to promote the conversion of gays, lesbians, and bisexuals to heterosexuality through reparative therapy. After 35 years of activity, they finally understood that that their efforts had little or no success; their clients were unable to change their sexual orientation. Exodus did have some success at convincing clients to remain sexually inactive. They closed their office and apologized for the harm that they had done to their clients in the past. More details about Exodus International.

Determining the precise cause(s) of sexual orientation might go a long way to inspire dialogue and eventually to resolve the remaining conflicts.

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Topics covered in this section:

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Sponsored link:

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Related essay:

bullet Divergent beliefs: Is homosexuality permanent? is it a choice that can be changed, or a fixed orientation?

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  1. Ned Flaherty, comment posted after the article "Gay Marriage: If Being Gay is a Choice, So What?" by Alasdair Denvil, PolicyMic, 2013-MAY-14, at: http://www.policymic.com
  2. "Why is my child Gay?" Parents and Friends of Lesbians and Gays (PFLAG) at: http://www.dynapolis.com/PFLAG/whygay.html
  3. "How PFOX can help," Parents & Friends of Ex-Gays, at: http://www.pfox.org/help.html 
  4. Athenadorus, "Homosexuality: Its Genetic Basis & Evolutionary Benefit," at: http://www.danaanpress.com/
  5. Matt Ridley, "Nature via nurture: Genes, experience, and what makes us human," HarperCollins, (2003). Read reviews or order this book safely from Amazon.com online book store  This book discusses the effects of genes and the environment on human behavior and traits. It touches on homosexuality in a few locations.
  6. "Sylvia," "The biological basis of homosexuality," 1997-DEC, at: http://www.geocities.com/
  7. "Science Proves that You Actually Can Tell Someone Is Gay Just By Looking At Them," Cozzoo, 2018-APR-07, at: blogs/news/science-proves-that-you-actually-can-tell-someone-is-gay-just-by-looking-at-them
  8. Nolan McCaskill, "Poll: 64 percent of Americans support same-sex marriage," 2017-MAY-15, at: https://www.politico.com/
  9. Aamer Madhani, "Poll: Approval of same-sex marriage in U.S. reaches new high," USA Today, 2018-MAY-23, at: https://www.usatoday.com/
  10. Andrea Gamna et al., "Large-scale GWAS reveals insights into the genetic architecture of same-sex sexual behavior," Science, 2019-AUG-20. Can be downloaded at: https://geneticsexbehavior.info/
  11. "A 'Gay Gene':" SimpliSafe emailing, 2019-AUG-30, at:DailyDigest@email.join1440.com
  12. "What we found and limitations," Genetic Sex Behavior, 2019, at: https://geneticsexbehavior.info/

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Copyright 1997 to 2019 by Ontario Consultants on Religious Tolerance
Latest update: 2019-SEP-04
Author: B.A. Robinson

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