Sexual dimorphism in digit‐length ratios of laboratory mice

  title={Sexual dimorphism in digit‐length ratios of laboratory mice},
  author={Windy M. Brown and Christopher J Finn and S. Marc Breedlove},
  journal={The Anatomical Record},
The lengths of the index finger (2D) and ring finger (4D) are sexually dimorphic in humans, and men have a smaller 2D:4D ratio compared to women. Prenatal androgens appear to be important in the development of the 2D:4D sex difference, since it has been reported in children as young as 2 years old, and since humans exposed to supernormal prenatal androgen levels display a smaller 2D:4D ratio. We tested whether another mammalian species in which the process of peripheral sexual differentiation… 

Digit ratio ( 2 D : 4 D ) and behavioral differences between inbred mouse strains

Large differences in digit ratio between the hind paw digit ratio in mice of eight inbred strains are found and it is suggested that inbred mice are a promising system for investigating the correlation between digit ratio and behavioral traits.

Digit ratio (2D:4D) and behavioral differences between inbred mouse strains

Large differences in digit ratio between the strains are found and it is suggested that inbred mice are a promising system for investigating the correlation between digit ratio and behavioral traits.

Sexual dimorphism in digit length ratios in two lizard species.

  • D. RuboliniF. Pupin N. Saino
  • Biology, Environmental Science
    The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology
  • 2006
These findings provide the first evidence that digit ratios are sexually dimorphic in any reptile species and are consistent with the idea that the genetic link between limb development and the urogenital system had been established with the evolution of the earliest terrestrial tetrapods.

Intrauterine Position Effects on Anogenital Distance and Digit Ratio in Male and Female Mice

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.

Avian hind‐limb digit length ratios measured from radiographs are sexually dimorphic

These findings show for the first time in avian species that sex differences in digit ratios have an osteometric basis, a fundamental prerequisite for a role of Hox genes in originating such dimorphism.

Digit Ratio (2D∶4D) Differences between 20 Strains of Inbred Mice

The inbred mice model presents an opportunity for researchers to investigate the genetic, and gene-environmental influence on the development of digit ratios, and calls into question the use of this trait as a broadly applicable indicator for prenatal androgen exposure.

Sexual dimorphism in digit length ratios of the second to fourth digits (2D:4D) in Blanford's fringe-toed lizard Acanthodactylus blanfordi Boulenger, 1918 (Sauria: Lacertidae) in the south of Iran

Sexual dimorphism in the length of the fingers was observed only in 2D: 4D on the right side of the body in forelimbs and hindlimbs, and the value of this trait was higher in males than females and this difference was statistically significant P ≤0.05.

Digit ratios in two lacertid lizards: sexual dimorphism and morphological and physiological correlates

Comparing digit ratios of two Podarcis lizards among sexes, colour morphs and species concludes that digit ratios in lizards deserve attention, because they exhibit sexual dimorphism and correlate with ecologically relevant morphological and performance variables.

Study of Sexual Dimorphism in Second-to-fourth Digit Length Ratio (2D: 4D) in the Green-Bellied Lizard (Darevskia cholorogaster) from Iran

The digits ratios observed in D. cholorogaster could be referred to microhabitat use by this species on different surfaces, besides basic genetic pattern and other ecological effects as foraging and mating, and supported a genetic pattern seen in humans and most mammals, inconsistent withbasic genetic pattern in reptiles.



The ratio of 2nd to 4th digit length: a predictor of sperm numbers and concentrations of testosterone, luteinizing hormone and oestrogen.

It is shown that 2D:4D in right and left hands has a sexually dimorphic pattern and is probably established in utero, which raises the possibility that patterns of digit formation may relate to spermatogenesis and hormonal concentrations.

Finger-length ratios and sexual orientation

The androgen-sensitive pattern of finger lengths is examined, and there is evidence that homosexual women are exposed to more prenatal androgen than heterosexual women are, and men with more than one older brother, who are more likely than first-born males to be homosexual in adulthood, are exposure to more pregnancies than eldest sons.

Sex difference and laterality in the volume of mouse dentate gyrus granule cell layer

The 2nd to 4th digit ratio and autism.

2D:4D ratio may be a possible marker for autism which could implicate prenatal testosterone in its aetiology, and there were positive associations of children with autism and the ratios of their relatives.

Possible sex differences in the developing human fetal brain.

The hypothesis that testosterone in utero may lead to a more rapidrowth of the right hemisphere or, alternatively, retard the growth of the left hemisphere is supported.

The Orthodox View of Brain Sexual Differentiation

The mechanisms underlying sexual differentiation of what may be the simplest mammalian model, the spinal nucleus of the bulbocavernosus (SNB), are reviewed, finding that the SNB system displays a far richer array of interactions than the standard view of sexual differentiation would predict.

Early prenatal attainment of adult metacarpal-phalangeal rankings and proportions.

Micrometric measurements of optically-projected histological hand sections show relative elongation of the distals between the 15-29 mm and 30-44 mm crown-rump range, and relative reduction to radiogrammetrically-determined adult proportions by the 90-104 mm CRL.

Proliferative lesions and reproductive tract tumors in male descendants of mice exposed developmentally to diethylstilbestrol.

Data suggest that, while fertility of the DES F(2) mice appeared unaltered, increased susceptibility for tumors is transmitted from the DES 'grandmothers' to subsequent generations.

Early Androgens Are Related to Childhood Sex-Typed Toy Preferences

Girls with congenital adrenal hyperplasia who were exposed to high levels of androgen in the prenatal and early postnatal periods showed increased play with boys” toys and reduced play with girls' toys compared with their unexposed female relatives at ages 3 to 8, suggesting that early hormone exposure in females has a masculinizing effect on sex-typed toy preferences.