Born This Way: - PowerPoint Presentation

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Born This Way:Homosexuality, Science, the Scriptures

Dr. J. Alan Branch

Midwestern Baptist Theological SeminarySlide2

Lady Gaga No matter gay, straight or biLesbian, transgendered life

I’m

on the right track, baby

I was born to surviveNo matter black, white, or beigeChola or orient madeI’m on the right track babyI was born to be braveSlide3

Lady Gaga I’m beautiful in my wayCause God makes no mistakesI’m on the right track, baby

I was born this waySlide4

Talking PointsHomosexuality is not a trait like skin color.Correlation does not equal causation.No trait has been discovered which is both necessary and sufficient for homosexuality.

Predisposition doesn’t equal

predetermination

.Slide5

I. Prenatal HormonesSlide6

Troy Perry, MCC FounderOne thing is certain about me: I feel I have a total sense memory that predates my birth by a good long time. It’s like being a seedling soul in two parts, your mother’s and your father’s genes. I have an awareness of having been a seedling – a physical presence in my father’s sperm and in my mother’s ovum before they were united. Troy Perry,

The Lord is My Shepherd and He Knows I’m Gay

(Los Angeles: Nash Publishing, 1972), 10. Slide7

A. Prenatal Hormones Theory

Hormones drive sexual development.

Homosexuals got the correct gender-specific hormones during genital development.

Homosexuals got the discordant hormone for their sex during brain development. (Boys got the girls’ hormones and girls got the boys’ hormones.)Slide8

B. Often Based on Animal ResearchAnimals act instinctively; humans are volitional. Slide9

C. Disorders of Sexual Development Only Show Weak to Possibly Moderate SupportNo ethical way to perform experiments on humans to

prove the theory.

Disorders of Sexual Development provide “natural” experiments.

Congenital Adrenal Hyperplasia (CAH): Body produces too much androgen and girls can develop genitalia with male characteristics. Slide10

C. Disorders of Sexual Development Only Show Weak to Possibly Moderate SupportLarge majority of girls with CAH self-identify as heterosexual

A higher percentage self-identify as homosexual than in the normal population.

Hard to disentangle genetic influence from social experience of growing up with a DSD.

Does not prove that prenatal hormones explain the development of a homosexual identification in most cases.Slide11

II. Do Homosexuals Have Different Brain Structures Than Heterosexuals?Slide12

A. Theory StatedSame-Sex attraction is caused by men having brain structures more similar to the average woman and women having brain structures more similar to the average man.Slide13

B. Simon LeVay, 1991 Neuroanatomist with

the Salk

institute; later with the

Institute of Gay and Lesbian Education.Examined the interstitial nucleus of the anterior hypothalamus (INAH): four cell groups known as INAH 1, 2, 3, and 4.Slide14
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Photo of INAH 3 from 2008 Study Slide17

B. Simon LeVay, 1991 41 cadavers,

LeVay

identified 19 of cadavers as homosexual males (including one bisexual);16 as heterosexual men; 6 as heterosexual women.

He claimed the INAH 3 cell group was more than twice as large in heterosexual men than in women and homosexual men. Slide18

C. Response and Critique LeVay’s own data demonstrates a weakness in the claim. Slide19

C. Response and Critique Some of the homosexual men had an INAH 3 similar in size to the majority of heterosexuals. A particular INAH 3 size is not necessary to cause homosexuality.Some of the heterosexual men had an INAH 3 similar in size to the majority of homosexuals. A particular INAH 3 size is not sufficient to cause homosexuality. Slide20

C. Response and Critique William Byne, director of the Neuroanatomy and

Morphometrics

Laboratory at the Icahn School of Medicine at Mount Sinai 2001.

No difference in number of neurons, but they seem to be packed more tightly in homosexual males. Slide21

C. Response and Critique “Based on the results of the present study as well as those of LeVay, sexual orientation cannot be reliably predicted on the basis of INAH3 volume alone.”

Byne

, et al, “The Interstitial Nuclei of the Human Anterior Hypothalamus,” 2001, 91. Slide22

C. Response and Critique Since 1991, no clear replication of LeVay’s results. Slide23

C. Response and Critique Generally, men have a higher percentage of white matter, and women a higher percentage of gray matter. No difference discovered here for homosexualsSlide24

III. What Can We Learn From Twin Studies?Slide25

A. Bailey and Pillard (1991)Identical and Non-Identical Male Twins

Found

that if one identical twin is homosexual, there is a 52% chance the other identical twin will be homosexual as well.

But between non-identical twins, there was only a 22% correspondence for homosexuality.We now know this data is inaccurate. Slide26

B. Bailey, Dunne, and Martin – 2000

Shows 1991 data was inaccurate.

Used

a much larger sample of Australian twins. Only 20% correspondence for Homosexuality among identical male twins. 24% correspondence for homosexuality among identical female twins.2010 Swedish Twin Study: Similar Results.Slide27

C. Response If one identical twin is homosexual, the chances the co-twin will also be homosexual is much higher than in the average population.But the vast majority of co-twins are not homosexual. This higher occurrence demonstrates the plausibility of some genetic factor exhibiting a low level of influence. Slide28

C. Response Actually strongly questions the “Born This Way” claim.If homosexuality were completely genetic, there would be 100% correspondence. Homosexuality is not a trait like hair or skin color.Slide29

IV. Has Science Discovered a Gay Gene?Slide30

A. Theory Stated People are homosexual because of a gene or genes that causes homosexuality in manner similar to the way genes code for skin color or eye color. Slide31

B. Dean Hamer, 1993Director of the Gene Structure and Regulation section at the National Cancer Institute.A sample of 40 pairs of homosexual brothers. C

laimed 33 of 40 pairs of homosexual brothers had co-inherited genetic information in the X-chromosome in a

region

called “Xq28”.Slide32

B. Dean Hamer, 1993Hamer did not claim to find a gay gene, he claimed to find a region on a chromosome where a “gay gene”

might

exist.

There are lots of genes in the Xq28 region. 1995; could find nothing for females. Some heterosexual males shared something at Xq28. Slide33

B. Dean Hamer, 1993“Even within the selected population that was studied, the Xq28 region was neither necessary nor sufficient for homosexual orientation.” Hamer’s team, 1995Slide34
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C. Sanders, Bailey, Et Al 2015Sanders with the University of Chicago; Bailey is the same guy from Twin Studies

409 pairs of gay brothers from 384 families

Two regions of

linkage identified: One area on Chromosome 8 (8q12) and Xq28Claim to have replicated Hamer’s dataSlide36

D. Response and Critique Using Genetic Linkage Analysis: Points to a Region and not specific base-pairs in the DNA.Neither Hamer nor Sanders/Bailey were claiming to have found a specific gene.In both cases,

the genetic sequence at Xq28 was different among each of the pairs of brothers.

What was common was the

location of the sequences. Slide37

D. Response and Critique Sanders and Bailey admit their results have weak predictive power. “Regarding any scenario that research in this area will result in a prenatal genetic test for homosexuality, the small magnitude of effects suggested herein are inconsistent with a test that those motivated to influence their children’s sexual orientation would find useful.”

Admit data on Xq28 actually just below threshold for significance. Slide38

D. Response and Critique 2012 study presented at the American Society of Human Genetics by the 23andMe database. (Private Company)More modern and precise, genome-wide association study.

23,000 individuals.

No

linkages reaching genome-wide significance for same-sex sexual identity for males or females.Slide39

D. Response and Critique No one has discovered a “gay gene.”Some regions of possible interest for some males in particular samples, but no areas of interest ever discovered for females. Slide40

V. Does Having More Older Brothers Make Someone Gay? Slide41

A. Theory Stated Each older brother increases the odds of homosexuality by 33%. Theory claims 1 out of 7 homosexual men can attribute same-sex attraction to the fraternal birth order effect.Slide42

B. ResponseProblems with the source of the samples.2006 study of entire population of Denmark found no substantial birth order effect. Half or more of all homosexual men have zero older brothers. Slide43

Summary Contrary to popular opinion, scientific research has not found a “gay gene.”Slide44

Summary There is no conclusive evidence that homosexuals have a substantially different brain structure than heterosexuals. Slide45

Summary A survey of modern scientific research demonstrates there are some factors with a low level of influence that correlate with a higher incidence of homosexuality among some populations.

However, no biological or genetic factors have yet been discovered that

cause

homosexuality.Correlation does not equal causation. Slide46

Linda Diamond of the University of Utah, Oct. 27, 2013Pro-Homosexual

“I feel as a community, the queers have got to stop saying, ‘Please help us. We’re born this way and we can’t change’ as an argument for legal standing. I don’t think we need that argument, and that argument is going to bite us in the [rear end], because we know that there’s enough data out there, that the other side is aware of it as much as we are aware of it.” Slide47

Born This Way:Homosexuality, Science, the Scriptures

Dr. J. Alan Branch

Midwestern Baptist Theological Seminary