Typical female 2nd–4th finger length (2D:4D) ratios in male-to-female transsexuals—possible implications for prenatal androgen exposure

@article{Schneider2006TypicalF2,
  title={Typical female 2nd–4th finger length (2D:4D) ratios in male-to-female transsexuals—possible implications for prenatal androgen exposure},
  author={Harald J{\"o}rn Schneider and Johanna Pickel and G{\"u}nter Stalla},
  journal={Psychoneuroendocrinology},
  year={2006},
  volume={31},
  pages={265-269}
}
THE BIOLOGIC BASIS OF TRANSGENDER IDENTITY: 2D:4D FINGER LENGTH RATIOS IMPLICATE A ROLE FOR PRENATAL ANDROGEN ACTIVITY.
  • M. Leinung, Christina Wu
  • Medicine
    Endocrine practice : official journal of the American College of Endocrinology and the American Association of Clinical Endocrinologists
  • 2017
TLDR
The findings are consistent with a biologic basis for transgender identity and the possibilities that FTM gender identity is affected by prenatal androgen activity but that MTF transgender identity has a different basis.
2D:4D Digit Ratios in Adults with Gender Dysphoria: A Comparison to Their Unaffected Same-Sex Heterosexual Siblings, Cisgender Heterosexual Men, and Cisgender Heterosexual Women.
We compared gender dysphoria (GD) patients and their same-sex siblings in terms of their 2D:4D ratios, which may reflect prenatal exposure to androgen, one of the possible etiological mechanisms
Finger Length Ratios in Serbian Transsexuals
TLDR
Results of the study go in favour of the biological aetiology of transsexualism.
Sexual Dimorphism in the Prenatal Digit Ratio (2D:4D)
TLDR
The 2D:4D ratio, thus, seems to increase after birth in both men and women, with the second digit growing faster than the fourth digit (positive allometric growth of digit two) and perhaps more so in women than in men.
Digit ratio (2D:4D) and transgender identity: new original data and a meta-analysis
TLDR
This original investigation and the updated meta-analysis clarify the association between transgender identity and 2D:4D indicating the influence of prenatal androgen on the development of gender identity in subjects born as males.
STUDYING THE RATIO OF SECOND FINGER ( FOREFINGER ) TO FOURTH ONE ( RING FINGER ) AMONG ORDINARY PEOPLE IN SOUTH KHORASAN PROVINCE AND COMPARING IT WITH 2 D : 4 D RATIO OF PROFESSIONAL THIEVES IN BIRJAND CENTRAL JAIL
TLDR
It is too likely that the amount testosterone among thieves is higher than ordinary population and thieved are likely commit offence due to further manly hormones.
The relationship between second-to-fourth digit ratio and female gender identity.
TLDR
The finger length ratio 2D : 4D in GID-FtM was significantly lower than in female controls in the right hand and 2D: 4D showed a positive correlation with GIS score.
2D:4D Suggests a Role of Prenatal Testosterone in Gender Dysphoria
TLDR
The findings support the idea that high levels of prenatal T in natal females and low levels inNatal males play a part in the etiology of GD, and add to the evidence demonstrating the convergent validity of 2D:4D as a marker of prenatalT effects.
Digit Ratio (2D:4D), Transgendered Belief, and Transsexual Drug Therapy in the BBC Internet Study
Transgendered belief—the conviction that one is the opposite gender to one’s natal gender—may be influenced by prenatal sex steroids. We consider this possibility by examining the relationship
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Findings add to evidence that prenatal hormonal factors may be linked to men's sexual orientation as well as ethnic groups, after ethnicity was taken into account.
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TLDR
2D:4D ratios determined directly from radiographs of the left hand confirm significant differences between males and females, however, female patients with virilizing CAH do not have a male digit ratio pattern suggesting that in theleft hand digit ratio development is not influenced by in-utero exposure to androgens.
Sexual orientation and the 2nd to 4th finger length ratio: evidence for organising effects of sex hormones or developmental instability?
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Results are consistent with the idea that prenatal androgen exposure reduces the 2D:4D and plays a role in the establishment of the sex difference in human finger length patterns, and finger lengths may offer a retrospective marker of perinatal androgens exposure in humans.
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Testosterone, particularly prenatal testosterone, has been implicated in the aetiology of many extragenital sexually dimorphic traits and it is suggested that the 2D:4D ratio may be associated with the expression of other sexuallyDimorphic behavioural traits.
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Handedness provides an accessible behavioral marker that may clarify the origin of disturbed gender identity and two sources of increased sinistrality allow us to better understand prenatal and perinatal stressors.
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