Finger-length ratios show evidence of prenatal hormone-transfer between opposite-sex twins.
نویسندگان
چکیده
Finger-length ratio (second to fourth finger; 2D:4D) has been associated with various measures thought to be related to prenatal androgens. In addition, hormone-transfer theory posits that hormones can transfer between twins. We examined 2D:4D in same-sex (SS) and opposite-sex (OS) dizygotic twins to test both propositions. Results show that 2D:4D is masculinized in OS females compared to SS females. This provides strong evidence that 2D:4D is laid down prenatally, and that hormones (likely androgens) can transfer from male to female fetuses. Implications for developmental timeframes for both hormone-transfer and 2D:4D are discussed.
منابع مشابه
No effects of prenatal hormone transfer on digit ratio in a large sample of same- and opposite-sex dizygotic twins
Hormone-transfer theory proposes that the hormonal milieu of one twin may influence the other. In opposite-sex twins it has been proposed that hormonal transfer may produce a masculinizing effect in females. The second-to-fourth-finger ratio (2D:4D) has been proposed as an index of the level of prenatal androgens and could, theoretically, be used to detect hormone transfer. Previous examination...
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ورودعنوان ژورنال:
- Hormones and behavior
دوره 49 3 شماره
صفحات -
تاریخ انتشار 2006