Finger Length Ratios of Identical Twins with Discordant Sexual Orientations

  title={Finger Length Ratios of Identical Twins with Discordant Sexual Orientations},
  author={Tuesday M. Watts and Luke Holmes and Jamie Raines and Sheina Orbell and Gerulf Rieger},
  journal={Archives of Sexual Behavior},
A proposed marker of prenatal androgen exposure is the ratio of the index finger to ring finger (2D:4D). Within each sex, this ratio may be lower for those who were exposed to higher levels of androgens and become attracted to women, as compared to those who were exposed to lower levels of androgens and become attracted to men. We examined these patterns in identical twins with discordant sexual orientations. Because these twins are genetically identical, differences in prenatal androgen… 
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