Finger-Length Ratios in Female Monozygotic Twins Discordant for Sexual Orientation
@article{Hall2003FingerLengthRI, title={Finger-Length Ratios in Female Monozygotic Twins Discordant for Sexual Orientation}, author={Lynn S. Hall and Craig T. Love}, journal={Archives of Sexual Behavior}, year={2003}, volume={32}, pages={23-28} }
The second to fourth finger digit ratio (2D:4D ratio) is a sex-dimorphic characteristic in humans that may reflect relative levels of first trimester prenatal sex hormones. Low interdigital ratio has been associated with high levels of androgens. It has been reported in unrelated women that low 2D:4D ratio is associated with lesbian sexual orientation, but because of the nature of those samples, it was not possible to conclude whether lower ratio (and hypothetically, higher androgen levels) in…
72 Citations
Prenatal Influences on Sexual Orientation: Digit Ratio (2D:4D) and Number of Older Siblings
- PsychologyEvolutionary psychology : an international journal of evolutionary approaches to psychology and behavior
- 2011
Prenatal androgen levels are suggested to influence sexual orientation in both sexes. The 2D:4D digit ratio has been found to associate with sexual orientation, but published findings have often been…
Sexual orientation and the second to fourth finger length ratio: a meta-analysis in men and women.
- PsychologyBehavioral neuroscience
- 2010
It is found that heterosexual women had higher (more feminine) left- and right-hand 2D:4D than did lesbians, but there was no difference between heterosexual and gay men.
Genetic and Environmental Influences on 2D:4D Finger Length Ratios: A Study of Monozygotic and Dizygotic Male and Female Twins
- Psychology, BiologyArchives of sexual behavior
- 2008
Biometric model-fitting analyses indicated significant additive genetic and nonshared environmental influences on digit ratios in twins, and suggest greater similarity between 2D:4D ratios in MZ relative to DZ twins that can be accounted for by genetic and nontraditional environmental factors.
Intrauterine Position Effects on Anogenital Distance and Digit Ratio in Male and Female Mice
- Biology, PsychologyArchives of sexual behavior
- 2008
The lack of correlation between 2D:4D and AGDs in this mouse strain suggests that these two measures do not reflect a common influence of androgen exposure, and the possible roles of temporal and localized effects of masculinization are discussed.
The Discordant Development of Sexual Orientation in Identical Twins
- Psychology, Biology
- 2017
Results suggested that these twins differed in many (but not in all) correlates of their sexual orientation, suggesting non-genetic influences, however, there were also subtle similarities within pairs that pointed to potential familial influences.
Finger-length ratios show evidence of prenatal hormone-transfer between opposite-sex twins
- MedicineHormones and Behavior
- 2006
Sex dimorphism in digital formulae of children.
- PsychologyAmerican journal of physical anthropology
- 2006
Test for a sex difference in the relative lengths of the finger bones, including the second-to-fourth digit ratio (2D:4D), using left-hand radiographs taken in young children indicate that relative digit lengths are sex-dimorphic in children, and suggests that 3D: 4D may be a better marker of perinatal sex differentiation.
The Second to Fourth Digit Ratio (2D:4D) in a Japanese Twin Sample: Heritability, Prenatal Hormone Transfer, and Association with Sexual Orientation
- PsychologyArchives of sexual behavior
- 2012
The existence of non-shared environmental influences that affect both 2D:4D and sexual orientation are suggested, which are in the predicted direction according to the prenatal hormone transfer hypothesis.
Testing the prenatal androgen hypothesis: measuring digit ratios, sexual orientation, and spatial abilities in adults
- PsychologyHormones and Behavior
- 2005
Through a glass, darkly: Human digit ratios reflect prenatal androgens, imperfectly
- BiologyHormones and Behavior
- 2020
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