Naturally occuring sex homeones in M to F TS

[MarieTS]

Does anyone know of the definitive answer as to whether or not Male to Female transexuals have naturally lower testosterone levels? That would be prior to any hormonal therapy, of course.

[Melody Moore]

Hi Marie,

I dont think there is any markers in the testosterone levels of transsexuals to indicate much at all. I believe most transsexuals have a normal amount of testosterone. Personally I have always appeared androgynous all my life but I was also born an hermaphrodite who was assigned as a male soon after birth. Despite growing up & living most of my life with feminine boyish looks & some obvious female attributes, I am well endowed & fertile as a male so I have fathered 3 kids. A recent study has revealed that Male-to-Female Transsexuals Have Female Neuron Numbers in a Limbic Nucleus. (http://jcem.endojournals.org/cgi/content/full/85/5/2034)

[Byanca]

Dunno. I presume I have low testosterone levels, or some other abnormality. Low sperm production. Just trickles out, amount like the tip of a teaspoon. first at 16 there started to come a little bit out of it. Does not sprout(just a tiny bit on a very rare occasion, it's been years since that happened, spooking me like nothing else). I doubt it's functional to make babies. It's certainly nothing to do sex with. I don't have erections in the morning either, never did. And that's really good. It has happened on a few occasion, but I don't know why. I can still remember it. So not very pleasant. This isn't something that is well received if it happens by itself. So I'm generally lucky that I don't have to deal with this.

From what I have read, this is a bit abnormal.

[MarieTS]

Melody--thank you so much for linking such a scientific article. I really appreciate it! It's great to review such through research. I'm trying to break the code as to if there are true physiological markers that /predict TS likelihood

[Starling]

It's my understanding (or perhaps my misunderstanding) that the cause of sex/gender conflict is an anomaly in the hormone wash that occurs in the womb, and that the affected person has normal hormone production levels and develops normally in a physiological sense, along lines congruent with their primary sex characteristics, unless there is outside intervention.

There are conditions in which hormone levels are not normal, so it's entirely possible that an individual transsexual might have abnormal numbers.

I am using the term normal to mean usual or average, not as a value judgment.

:) Lallie

[Kathryn Martin]

There is a lot written about Muellerian Hormone in the determination of sex in embryos. In the 8th-9th weeks of gestation a hormone called Anti Muellerian Hormone (AMH) is produced in the testes of human embryos. The presence (male) or absence (female) of the hormone determines the development of the female sex organs or male sex organs. The testes develop in females into ovaries and in males into testicles. Because of that the following production of testosterone occurs in both the ovaries and the testicles following development except that ovaries produce much lower amounts than testicles. The adrenal glands in women produce another male hormone DHEA and other androgen.

Estrogen in males is produced by the testicles, the adrenal and pituitary glands in small amounts. It is needed for a whole variety of functions in the body.

There are certain indicators of lower testosterone levels in males. Full hair growth on the head as you get older, low amount of body hair, lower sex drive (although people never want to admit to it) etc. But of course it ia all relative compared to females levels. I think that the amount of testosterone in men is measured in small increments. Compared to females these differences are minuscule.

[CharleneT]

Only in that many MTF's start to deal with these issues later in life, when the amount of testosterone is naturally dropping anyhow.

Unfortunately there is very little research about TS folks at all !! We're just not interesting to the medical research scientists :Pullhair:

[Byanca]

Only in that many MTF's start to deal with these issues later in life, when the amount of testosterone is naturally dropping anyhow.

Mine should have been at the top about now. It's for sure destructive. But it appears to me that it could have been a whole lot worse.

I believe there are also connection to how one live. Eating little, no excersice etc. Soya products. Smoking and drinking. I believe all these things can brake down the production of testosterone. And make it easier on the body and get through the day. Not very healthy. But that is secondary imo.

[Starling]

...In the 8th-9th weeks of gestation a hormone called Anti Muellerian Hormone (AMH) is produced in the testes of human embryos. The presence (male) or absence (female) of the hormone determines the development of the female sex organs or male sex organs...

That's interesting, Kathryn. But you say AMH is a hormone that is already present in the fetus. What about the hormone(s) from the mother that enter the amniotic fluid? When we discuss TS, I believe, we're not talking about the development of sex organs, but the mental gender orientation.

:) Lallie

[Teri Jean]

I had the same thoughts and then I asked my endrocrynologist and I had a base line of 600 which is midpoint and now it runs 8.7 where the door slammed shut. (-: Having said that it seems not to be the case that lower levels of testosterone has anything to do with the fact we are TS.

[Kathryn Martin]

That's interesting, Kathryn. But you say AMH is a hormone that is already present in the fetus. What about the hormone(s) from the mother that enter the amniotic fluid? When we discuss TS, I believe, we're not talking about the development of sex organs, but the mental gender orientation.

:) Lallie

AMH is formed and produced in the embryonic testes. Here is a excerpt from Dr. Shuvo Gosh, MD Assistant Professor at the university Clinic in Montreal:

"Initially, all human fetuses are primed to have a female sex, in that the default pathway for development is toward female anatomy. During the eighth week of gestation, fetuses with a Y chromosome and a functional locus for the SRY gene product, also called the testes determining factor (TDF), undergo testicular development. This process converts the inherently female fetus into a male one, as a steadily increasing surge of testosterone is then produced by the testes. Much of the testosterone is converted to dihydrotestosterone, which is the key virilizing hormone during gestation. Along the biochemical pathway of hormone production, other recently identified gene products likely play an additional role in the masculinization of the fetus."

It is worth reading this article because it sets out in some detail what happens during gender determination. The article is Sexuality, Gender Identity (http://emedicine.medscape.com/article/917990-overview) I hope this helps a little.

Kathryn

[Starling]

Thank you for the article, Kathryn.

:) Lallie

[michelle2b]

I was close to the upper end the T range for genetic males before I started blocking my DHT. DHT blockers made my T levels go above the range for genetic males. Perhaps owing to high T and DHT, I had no physical inadequacies and no infertility. And I do enjoy sex. However, I have gender dysphoria. I doubt I am the only exception if the theory you stated were true. I think it is a mere myth that MTF transsexuals must somehow be less biologically "male" (low T, small genital sizes, infertile, impotent, etc) per the societally accepted definition of "male". I think the root cause lay somewhere else, for example as the article link from Melody states - MTF trans people are typically genetically and biologically within the "normal" range (as in statistical normal distribution) for genetic males, but there's a difference in neural structure that makes us different from cis-gender males.

[MarieTS]

Kathryn, Michelle, Lallie, Teri Jean, Melody, Byanaca, Charlene et al., I continue to thank you for your eye-openning insights and research. I couldn't help but think there has to be some hormonal difference with us (from birth) but the excellent papers indicate otherwise. The clues, indicators, and reasons why must reside elsewhere.
So much for the short vs. long pointer/ring finger theory, huh?
The dysphoria descriptions really rang true. I just thought that there would be some physical connection/symptoms (hormonal levels, perhaps as evidenced through blood levels and finger length) that go hand-in-hand with the mental/emotional outlook. Guess not. SO, if it is just in our heads, it must just the same reside in the clues like our AMH and Limbic Nucleus and elsewhere.
I continue to be greatful for your perspectives and thoughts :hugs:

[Kathryn Martin]

SO, if it is just in our heads, it must just the same reside in the clues like our AMH and Limbic Nucleus and elsewhere.


I don't think it is just in our heads at all. I do think that the answer is not simplistic. I think that part of the clues to look for is the socialization of the infant by the parents. You will see the statement I made in my signature. If there is a confluence of a biological pre-disposition, such as a light case or partial androgen sensitivity syndrome and gender unspecific socialization keeping so to speak the options open for a much longer time, it is possible if not inevitable that the person feels different than what the majority feels like. The other point here that it is not a condition but in fact an expression of potential that is anchored within the development spectrum of every human being.

One other point. I believe, that maybe the female cells found in the limbic nucleus are more a result of early fetal development gestures rather than the cause. It then of course will influence the further development of the fetus, infant and adult. Not that it matters much, but I thought I say it anyway. This is a great thread by the way, and I thank you for bringing it to us.

[Byanca]

[COLOR="teal"]I just thought that there would be some physical connection/symptoms (hormonal levels, perhaps as evidenced through blood levels and finger length) that go hand-in-hand with the mental/emotional outlook. Guess not. SO, if it is just in our heads, it must just the same reside in the clues like our AMH and Limbic Nucleus and elsewhere.

My ring finger and pointing finger is the same lenght. Pointing to low testosterone levels. I'm also 3'rd born with 2 older brothers. Consieved just after my brother, so the woomb was probably soaked with estrogen.

I believe estrogen whashings in the woomb is for sure going to make one more female, even if it appears that one is a male.

[Kathryn Martin]

My ring finger and pointing finger is the same lenght. Pointing to low testosterone levels. I'm also 3'rd born with 2 older brothers. Consieved just after my brother, so the woomb was probably soaked with estrogen.

I believe estrogen whashings in the woomb is for sure going to make one more female, even if it appears that one is a male.

Wow I just did a quick research and the 2D:4D digit ration has been the subject of a lot of serious research. Apparently, the male ratio is .98 and the female ration is 1.0 in the right hand if RH is the dominant hand. Mine is 1.0129 which is an indicator of:

"The dimorphism is present from at least age 2 years and 2D:4D is probably established in utero; (ii) high 2D:4D ratio in right hands was associated with germ cell failure in men (P = 0.04); (iii) sperm number was negatively related to 2D:4D in the right hand (P = 0.004); (iv) in men testosterone concentrations were negatively related to right hand 2D:4D and in women and men LH (right hand), oestrogen (right and left hands) and prolactin (right hand) concentrations were positively correlated with 2D:4D ratio and (v) 2D:4D ratio in right hands remained positively related to luteinizing hormone and oestrogen after controlling for sex, age, height and weight. "

(c) The ratio of 2nd to 4th digit length: a predictor of sperm numbers and concentrations of testosterone, luteinizing hormone and oestrogen.
1. J T Manning (http://humrep.oxfordjournals.org/search?author1=J+T+Manning&sortspec=date&submit=Submit),
2. D Scutt (http://humrep.oxfordjournals.org/search?author1=D+Scutt&sortspec=date&submit=Submit),
3. J Wilson (http://humrep.oxfordjournals.org/search?author1=J+Wilson&sortspec=date&submit=Submit) and
4. D I Lewis-Jones (http://humrep.oxfordjournals.org/search?author1=D+I+Lewis-Jones&sortspec=date&submit=Submit)

This is really quite enlightening in many ways. This could be the beginning of a phenomenology of Transsexualism. In my view this is what research should concentrate on, because ultimately it, together with anecdotal description of individuals and common traits would give a much better insight to who we are for humanity at large. It is still dealing more with the effects, but at least there is some confirmation that it's not just in the head:D but in the hands as well:thumbsup: and first and foremost in the heart:<3: I love us:o

Thanks Bianca

[CharleneT]

Well . . . my right hand fits the female model and my left the male ?? SO I am genetically confused :lol: !!

[Zenith]

...Unfortunately there is very little research about TS folks at all !! We're just not interesting to the medical research scientists :Pullhair:

Having a background in research, (as you), I can say that TS are probably very interesting. Much effort is undergone to create mutations in order to disrupt a natural mechanism and study the effects. The problem is of course politics. Very unlikely to get funding for studies on such an unpopular and misunderstood subject by the mainstream (at least in the US).

[CharleneT]

My older brother is a geneticist, so I figured it was worth asking him about this issue. SO, here is an answer from a real life expert ;) :

"That is one that keeps popping up. A good article to read on it is in Wikipedia (http://en.wikipedia.org/wiki/Digit_ratio ). There are sex, ethnic, and claims of sexual orientation factors affecting it. Note that the ethnic influences can be important too. However, even birth order has an effect (http://www.unl.edu/rhames/courses/readings/homofinger/homo_finger.html).

For the record, my index (2nd digit) is shorter than my ring (4th digit) on both hands. Make sure that you are using the correct numbers: thumb is 1, index is 2, etc. Measurement needs to be done with the appropriate digit in exact linear alignment with the metacarpals and carpals to which it extends from--it is easy to get the ratio off a bit by touching the sides of your fingers together and tilting fingers a bit. AND I bet that a standard starting point should be the middle of the knuckle but there may be some ambiguity in determining that. Therefore, the error in ratios is fairly big and might influence the conclusions of some studies such as the one on gay men. In fact, if you look at the figures in that paper, the standard deviations are fairly large fractions of the mean measurements; i.e.there is a LOT of variation within each group making a measurement of a given individual a risky way to backtrack into telling what sex/sexual orientation/etc they are (from the 2d::4d ratio). In particular, note from fig 1a that some heterosexual men (actually a LOT of them) will have ratios identical to many lesbians and gay men.

Another aspect to keep in mind is that sex hormone exposure in utero is thought to control this ratio but, like most developmental features, not exclusively. Therefore, other 'causes' could come into play; breaking a bone or various diseases can lead to deformation (and affect length)--especially possible when the hands differ markedly. I doubt most of those studies have corrected for effects of smoking or alcohol, in utero, either.

Sorry, I went on so long. Too easy for me to look at this kind of information and think about its limitations. The bottom line is true: men often have shorter 2d than 4d and women often have 2d = 4d. "


---> Julie: quite right indeed ! Unfortunately another fact is that the dollars spent on research for all women's issues are disproportionately low. I mean really low ! Which is of course absurd considering - just for starters - there are more women than men to begin with !

[Kaitlyn Michele]

Julie i think you are right...our teeny tiny population and the politics around it also makes it very hard to make a living in the cis-world, and even harder to make a living in businesses catering to trans people...and especially hard to make a living for scientists studying us...i'm not a scientist so perhaps i'm overstating that last point, but money does make the world go round

one thing i have found is that asking why has become much less important as transition grinds on. It's definitely one of the benefits of transition i think because the question of why truly haunted me for my entire life!!!

.. its not like its a disease, so the benefits of identifying the "root" causes are what exactly?? in fact, i worry more that we would have all been eradicated if there was some kind of genetic test to tell a mom that her baby was going to be transsexual..
i don't think the political and social treatment of transsexuals would change much if a cause was determined to be genetic and therefore not anybody's fault..the social difficulties around gender are soooo complicated! gender is central to our lives in just about every way..

I fear that the inability for a cisgender person to truly understand why on earth we are this way is permanent..and they are always going to think we are some too strange and marginalize us..

i just assume something happened either in my mothers womb, or i'm a genetic or hormanal "variant" or that my mom turned me into a girl when i was a baby (i rather doubt the last one)...in any case, the only thing i can think of as a benefit to id'ing the cause is to make me feel better about myself..and transition accomplished this for me in a big way.

i don't mean to sound negative...i'm not that way at all...i'm just saying i've become much more pragmatic..."it is what it is" is my final answer and i'm sticking with it!!

[Melody Moore]

Well, this digit ratio is a very interesting observation and here is a couple of
photos I just took of my own right hand showing the ratio of my 2nd & 4th digits

[MarieTS]

[COLOR="teal. [/COLOR]

[michelle2b]

The clues, indicators, and reasons why must reside elsewhere.
So much for the short vs. long pointer/ring finger theory, huh?
The dysphoria descriptions really rang true. I just thought that there would be some physical connection/symptoms (hormonal levels, perhaps as evidenced through blood levels and finger length) that go hand-in-hand with the mental/emotional outlook. Guess not. SO, if it is just in our heads, it must just the same reside in the clues like our AMH and Limbic Nucleus and elsewhere.
I continue to be greatful for your perspectives and thoughts :hugs:

If you are asking whether MTF trans people have "on the average" 2D:4D digit ratios closer to the heterosexual genetic females and heterosexual genetic males, then yes it is true. You must note though that it is probably more related to sexuality than gender, since homosexual and bisexual women tend to have digit ratios closer to the that of the average heterosexual genetic males. Of course there are exceptions (and that's the beauty of life in all its diversity).

However, if you are trying to figure out why you feel the way you do (ie. gender dysphoria), it is not because your finger digit ratios are closer to the average heterosexual genetic female. Your fingers do not make you feel more male or more female just as your toes do not make you feel more male or more female.

You feel gender dysphoria because something inside your brain makes you feel like you are more female or that you are less male. Without that neural structure in your brain, you may have never felt gender dysphoric. The explanation about the limbic system addresses that key point.

Your natural testosterone levels after birth, however low they may be, are unlikely to cause your gender dysphoria, just as a genetic cisgender male with naturally low testosterone has no gender dysphoria. The key point here is that while you have some neural structure in your brain, the genetic cisgender male does not have the same neural structure in his brain.

Finally, what caused your neural structure to be the way it is and your digit ratio to be the way it is has probably happened prior to your birth. While there are theories about what might have happened, it is hard to conclusively prove any at the present time. The problem is the lack of sufficient valid data. In a few years, we will figure it out with more women getting better medical care around the world (and with doctors keeping records of their pregnancies) and with trans people feeling slightly more free to be themselves in a gradually more accepting society.

Penis size most likely is related to your DHT levels during late childhood and adolescent years. DHT appears to trigger growth of genital structures in a male in addition to male secondary sex characteristics such as hair patterns and sebum production and skin texture. DHT levels are not necessarily proportional to T levels. DHT levels in your body are determined by the quantity of various enzymes that your body produces regardless of the level of T. Hence even when genetic males age, their DHT levels may remain high even if their T levels decline. Of course DHT is produced from T, so if you block DHT production in your body, your T levels will rise up. Likewise, if you block your T, your DHT levels will decline because there will be less T available to your body to produce DHT. Since our cells regenerate regularly and because DHT helps regeneration of cells in the male genital structures, if you take T blockers long enough (thereby blocking your DHT levels too), your penis size can shrink to a noticeable extent. The key point is that penis size is unlikely to cause your gender dysphoria.

I hope this helps explain many questions (and I am sure it will raise many more if you think about it).

[Melody Moore]

The problem is the lack of sufficient valid data. In a few years, we will figure it out with more women getting better medical care around the world (and with doctors keeping records of their pregnancies) and with trans people feeling slightly more free to be themselves in a gradually more accepting society.
They already have some valid data to now go on after creating transsexual mice :)

http://www.nature.com/news/2009/091210/full/news.2009.1135.html


In many mammals, sex is determined during the early development of the fetus by the activity of a gene called SRY located on the Y sex chromosome, carried only by males. That gene triggers a second gene, called SOX9, which induces testes development.

[Melody Moore]

I have just got an email from the Australian Transsexual Support Network about a study into what
potentially triggers transsexualism & homosexuality etc that is going to surprise a few people here.

Sexual differentiation of the human brain in relation to gender identity and sexual orientation (http://findarticles.com/p/articles/mi_7542/is_200901/ai_n32334584/?tag=content;col1)
Functional Neurology, Jan-Mar 2009 by Swaab, Dick F, Garcia-Falgueras, Alicia


Summary
During the intrauterine period the foetal brain develops in the male direction through a direct action of testosterone on the developing nerve cells, or in the female direction through the absence of this hormone surge. In this way, our gender identity (the conviction of belonging to the male or female gender) and sexual orientation are programmed into our brain structures when we are still in the womb. However, since sexual differentiation of the genitals takes place in the first two months of pregnancy and sexual differentiation of the brain starts in the second half of pregnancy, these two processes can be influenced independently, which may result in transsexuality. This also means that in the event of ambiguous sex at birth, the degree of masculinisation of the genitals may not reflect the degree of masculinisation of the brain.

There is no proof that social environment after birth has an effect on gender identity or sexual orientation.Read the fully study paper here: Sexual differentiation of the human brain in relation to gender identity and sexual orientation (http://findarticles.com/p/articles/mi_7542/is_200901/ai_n32334584/?tag=content;col1)

Another summary on this subject on wikipedia: Prenatal hormones and sexual orientation (http://en.wikipedia.org/wiki/Prenatal_hormones_and_sexual_orientation)

[Starling]

This is a very cool thread.

:thumbsup: Lallie

[Melody Moore]

If you want some more interesting reading about genetics, sex hormones and how they affect
our sexual orientation & development - here are some links to .pdf files on various related subjects

A Sex Difference in the Human Brain and its Relation to Transsexuality (http://shb-info.org/sitebuildercontent/sitebuilderfiles/brainsex.pdf) (Published in 1997)

SEXUAL DIFFERENTIATION OF THE HUMAN BRAIN (http://www.bgscb.org/Vol7-17-32.pdf) (Published in 1997)

A Sex Difference in the Human Brain and its Relation to Transsexuality (http://shb-info.org/sitebuildercontent/sitebuilderfiles/brainsex.pdf) (Published in 1997)

Male-to-Female Transsexuals Have Female Neuron Numbers in a Limbic Nucleus (http://jcem.endojournals.org/cgi/reprint/85/5/2034.pdf) (Published in 2002)

Sexual Differentiation of the Bed Nucleus of the Stria Terminalis in Humans May Extend into Adulthood (http://www.jneurosci.org/cgi/reprint/22/3/1027.pdf) (Published in 2002)

A sex difference in the hypothalamic uncinatenucleus: relationship to gender identity (http://brain.oxfordjournals.org/content/131/12/3132.full.pdf) (Published in 2008)

Sexual differentiation of the human brain in relation to gender identity and sexual orientation (http://www.keepandshare.com/doc/2317092/sexual-differentiation-of-the-human-brain-relating-to-gender-identity-sexual-orietation-pdf-oc?da=y) (Published in 2009)
HTML version - http://findarticles.com/p/articles/mi_7542/is_200901/ai_n32334584/

If you want to find more study papers on related subjects, please refer to the Reference sections on some of these papers for more detailed information.

[Melissa A.]

My Testosterone levels were very low before HRT. So much so, that my doctor felt compelled to call me and re-ask me if I had ever been on HRT before(wasn't). I am in no way saying that low T levels or any other physical uniqueness are necessary conditions to define a transsexual. Genetics affects us all in different ways. But it wouldn't surprise me if some of us are that way before we start.

Hugs,

Melissa:)

[Melody Moore]

My Testosterone levels were very low before HRT. So much so, that my doctor felt compelled to call me and re-ask me if I had ever been on HRT before(wasn't). I am in no way saying that low T levels or any other physical uniqueness are necessary conditions to define a transsexual. Genetics affects us all in different ways. But it wouldn't surprise me if some of us are that way before we start.
Doesn't surprise me at all, Ive noticed a few girls here that are remarkably feminine or androgynous & are not even on HRT or not for long. When I first went to see my specialist, the first thing she asked was I already having electrolysis when Ive never had any in my life. I told her that I have never had a heavy beard growth & dont have very much body hair either. I do however have a hair loss problem that started 7 years ago, which ironically was the same time I was put on steroids to treat a very serious lung infection - the steriods also caused me to bulk up with more muscle. Since starting HRT my hair loss problem has stopped & is also appears to be starting to actually grow back. :)

I went back the the sexual health clinic last Monday and I seen a different specialist, I told this doctor about the very rapid breast development & showed him, he was shocked and insisted on taking blood samples to check my oestrogen levels. He said they might have to put me on a much lower dosage.

[Melody Moore]

I thought I should revive this topic of discussion because it also contains lots of links to other relevant information to my other
topic on Surge in Intersex/TG & TS Numbers - Something in the food & water perhaps? (http://www.crossdressers.com/forums/showthread.php?143339-Surge-in-Intersex-TG-amp-TS-Numbers-Something-in-the-food-amp-water-perhaps) and Danni's topic on Gender Identity. (http://www.crossdressers.com/forums/showthread.php?143298-Gender-Identity)