scholarly journals Environmental levels of oestrogenic and antiandrogenic compounds feminize digit ratios in male rats and their unexposed male progeny

2013 ◽  
Vol 280 (1768) ◽  
pp. 20131532 ◽  
Author(s):  
Jacques Auger ◽  
Dominique Le Denmat ◽  
Raymond Berges ◽  
Ludivine Doridot ◽  
Benjamin Salmon ◽  
...  
Keyword(s):  
Sexual Dimorphism ◽  
Endocrine Disruptors ◽  
Digit Ratio ◽  
Male Rats ◽  
X Rays ◽  
Ratio Measurement ◽  
Male Progeny ◽  
Digit Ratios ◽  
Gestational Exposure ◽  
Prenatal Androgen

Digit length ratios, especially the second-to-fourth digit ratio (2D : 4D), are associated with various pathological and behavioural conditions in many species including humans and are dependent upon prenatal androgen to oestrogen balance. It is unknown whether digit ratios are modified by environmental exposure to ubiquitous endocrine disruptors . We studied the effect on adult male Wistar rat digit ratios of a gestational exposure to the oestrogenic and antiandrogenic compounds bisphenol A (BPA), genistein and vinclozolin, in low doses, and in combination with investigating in parallel a possible sexual dimorphism of this trait. We also investigated the effects on the male progeny not exposed during gestation. X-rays were taken of the left and right forepaws, and 2D–5D proximal to distal phalanx distances were measured by a standardized procedure based on semi-automatic image analysis. We provide evidence that there is a sexual dimorphism of digit ratios in the Wistar rat, and we found that BPA alone or in combination with genistein and vinclozolin significantly feminized digit ratios in male rats. Intriguingly, significant feminization of digit ratios was also found in the unexposed male progeny of males that had been exposed to compound mixtures. In conclusion, prenatal environmental levels of endocrine-active substances permanently disrupt digit ratios. Digit ratio measurement in adults is thus a promising biomarker of prenatal exposure to low-dose endocrine disruptors in rodents, with potential implications for future studies in humans.

scholarly journals Sex, population origin, age and average digit length as predictors of digit ratio in three large world populations

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marina Butovskaya ◽  
Valentina Burkova ◽  
Yulia Apalkova ◽  
Daria Dronova ◽  
Victoria Rostovtseva ◽  
...  
Keyword(s):  
Sexual Dimorphism ◽  
European Population ◽  
Digit Ratio ◽  
Age Cohorts ◽  
Digit Ratios ◽  
Linear Relationships ◽  
Large Populations ◽  
Age Cohort ◽  
Population Origin ◽  
Digit Length

AbstractRecently, a number of authors have claimed that sexual dimorphism in the second-to-fourth digit ratio (2D:4D) is simply dependent on digit length and is an artifact of allometry. The goal of our study is to verify the validity of these assumptions. The study sample comprised 7,582 individuals (3,802 men and 3,780 women) from three large world populations: Europeans (n = 3043), East Africans (n = 2844), and Central Asians (n = 1695). The lengths of the second and fourth digits on both hands were measured. Digit ratios were computed according to standard procedures. Analyses were conducted separately for each hand for the whole sample and in succession for the three large populations. Additionally, we separately tested four age cohorts (≤ 13, 14–18, 19–30, and 31 ≥ years) to test the effect of developmental allometry. The second and fourth digits showed strong positive linear relationships on both hands, and demonstrated an increase with age; digit length in women from the youngest age cohort was longer or equal to that of men, and shorter than men in older age cohorts. However, the 2D:4D magnitude and its sexual dimorphism remained stable throughout the ontogeny. To test for an allometric effect on 2D:4D, the average digit lengths were calculated. Both sex and population origin were permanent reliable predictors of 2D:4D, whereas average digit length was not. Height was applied as another measure of allometric effect on the limited sample (≤ 30 years) from the European population, along with sex and age. No allometric effect was observed in this case. We conclude that sex differences in 2D:4D are not an artifact of allometry.

scholarly journals Fingers as a Marker of Prenatal Androgen Exposure

Endocrinology ◽  
2009 ◽  
Vol 150 (11) ◽  
pp. 5119-5124 ◽  
Author(s):  
Sheri A. Berenbaum ◽  
Kristina Korman Bryk ◽  
Nicole Nowak ◽  
Charmian A. Quigley ◽  
Scott Moffat
Keyword(s):  
Androgen Insensitivity Syndrome ◽  
Digit Ratio ◽  
Complete Androgen Insensitivity Syndrome ◽  
Good Marker ◽  
Digit Ratios ◽  
Androgen Exposure ◽  
Prenatal Androgen Exposure ◽  
Hormone Exposure ◽  
Biological Substrates ◽  
Prenatal Androgen

Interest in biological substrates of sex-related variations in psychological and physiological characteristics has led to a search for biomarkers of prenatal hormone exposure that can be measured postnatally. There has been particular interest in digit ratio, the relative lengths of the second and fourth fingers (2D:4D), but its validity as a measure of prenatal androgen has not been established. We report the strongest evaluation of the value of 2D:4D as a biomarker for early androgen exposure. Individuals with 46,XY karyotype but no effective prenatal androgen exposure due to complete androgen insensitivity syndrome had digit ratios that were feminized: they were higher than those of typical men and similar to those of typical women. Nevertheless, the effect was modest in size, and there was considerable within-group variability and between-group overlap, indicating that digit ratio is not a good marker of individual differences in prenatal androgen exposure.

scholarly journals Digit ratio in three species of tropidurid lizards

Herpetozoa ◽  
2021 ◽  
Vol 34 ◽  
pp. 67-70
Author(s):  
Kelton Gonçalves Miranda ◽  
Marcella Junqueira Goulart ◽  
Conrado Barbosa Galdino
Keyword(s):  
Sexual Dimorphism ◽  
Sex Hormones ◽  
Digit Ratio ◽  
Sexually Dimorphic ◽  
Lizard Species ◽  
Finger Length ◽  
Digit Ratios ◽  
Selective Forces ◽  
Males And Females ◽  
Interpopulation Variation

Proportions between pairs of digits are linked to fitness in tetrapods and they can be influenced by sex hormones through individuals’ ontogenies. Therefore, in many species, the proportions amongst finger length ratios (referred as digit ratio, i.e. 2D second and 4D fourth digits) can differ between males and females. We investigated whether the three most commonly used forelimb digit ratios are sexually dimorphic in three tropidurid species. In one of the three lizard species, Eurolophosaurus nanuzae, males and females differ for only 2D:4D digit ratio. Otherwise, our results on the studied Tropidurus species conform to previous studies showing no differences in digit ratios between males and females. Hence, it might be the case of local selective forces shaping interpopulation variation in the expression of sexual dimorphism for digit ratio.

Exploration of alternative digit ratios as a predictor of prostate cancer aggressiveness.

2014 ◽  
Vol 32 (4_suppl) ◽  
pp. 231-231
Author(s):  
Michael Stolten ◽  
Elisa Ledet ◽  
Aryeneesh Dotiwala ◽  
Eric Luk ◽  
A. Oliver Sartor ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Age Of Onset ◽  
Digit Ratio ◽  
Finger Length ◽  
Digit Ratios ◽  
Androgen Exposure ◽  
Cancer Aggressiveness ◽  
Prenatal Androgen Exposure ◽  
Prenatal Androgen ◽  
Androgen Levels

231 Background: During gestation, development of the prostate is dependent on a functional androgen receptor and the presence of dihydrotestosterone. Prenatal androgen exposure has been correlated with a range of diseases including prostate cancer (PCa). Historically, the ratio of the second to the fourth digit (2D:4D) has been linked to prenatal androgen levels; however, the use of alternate finger ratios have been shown to be a greater indicator of prenatal androgen exposure compared to the traditional 2D:4D ratio. Studies have shown that the distal fingertip extent of the second digit (2T:2D) was also associated with prenatal androgens. This study aims to use alternative digit ratio measurements to determine aggressiveness of PCa. Our hypothesis is that alternative digit ratios are more sensitive to prenatal androgen levels, and a better predictor of disease than the traditional 2D:4D ratio. Methods: Digital measurements were made from hand scans of PCa patients. All fingers on the right hand were measured from the basal crease to the fingertip as well as the distal fingertip extent of the second digit. Race, family history (FH) (first degree relatives with PCa), and age at diagnosis were recorded. These clinical covariates were then compared to the finger length ratios which were dichotomized based on the median values and analyzed for possible correlations. Results: Hand measurements were taken on 350 Caucasian (CA) and 100 African American (AA) PCa patients. AA men were more likely to have a smaller 2D:3D (P < 0.0001) and 2D:4D digit ratio (P < 0.0001), and larger 3D:5D (P = 0.0002) and 4D:5D (P = 0.0125) when compared to CA men. AA men with a smaller 2T:2D ratio were younger at the time of diagnosis (P = 0.0446). Additionally, AA men with a larger 2D:5D ratio were more likely to have a FH of PCa (P= 0.0238). Conclusions: Alternative finger length ratios show strong differences between AA and CA men. In AA men, alternative digit ratios are associated with age of PCa diagnosis and FH of PCa. These hypothesis generating results require validation in a larger cohort, but may provide insight to the underlying racial disparity observed in PCa. Finger length may represent a unique, non-invasive predictor of PCa, specifically age of onset and FH in AA men.

scholarly journals Investigating the reliability and sex differences of digit lengths, ratios, and hand measures in infants

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Luisa Ernsten ◽  
Lisa M. Körner ◽  
Martin Heil ◽  
Gareth Richards ◽  
Nora K. Schaal
Keyword(s):  
Sex Differences ◽  
Measurement Techniques ◽  
Directional Asymmetry ◽  
Computer Assisted ◽  
Sexually Dimorphic ◽  
Digit Ratios ◽  
Androgen Exposure ◽  
Prenatal Androgen Exposure ◽  
Test Retest Reliability ◽  
Prenatal Androgen

AbstractHands and digits tend to be sexually dimorphic and may reflect prenatal androgen exposure. In the past years, the literature introduced several hand and digit measures, but there is a lack of studies in prepubertal cohorts. The available literature reports more heterogeneous findings in prepubertal compared to postpubertal cohorts. The comparability of the available studies is further limited by the study design and different measurement techniques. The present study compared the reliability and sex differences of available hand and digit measures, namely digit lengths of 2D, 3D, 4D, 5D, digit ratios 2D:4D, 2D:5D, 3D:4D, 3D:5D, 4D:5D, relative digit lengths rel2, rel3, rel4, rel5, directional asymmetry of right and left 2D:4D (Dr-l), hand width, length, and index of 399 male and 364 female 6-month-old German infants within one study using only indirect and computer-assisted measurements. The inter-examiner reliability was excellent while the test-retest reliability of hand scans was only moderate to high. Boys exhibited longer digits as well as wider and longer hands than girls, but smaller digit ratios, with ratios comprising the fifth digit revealing the largest effect sizes. Other hand and digit ratios revealed sex differences to some extent. The findings promote the assumption of sexual dimorphic hand and digit measures. However, by comparing the results of the available literature, there remains an uncertainty regarding the underlying hypothesis. Specifically in prepubertal cohorts, i.e. before the influence of fluctuating hormones, significant effects should be expected. It seems like other factors than the influence of prenatal androgens contribute to the sexual dimorphism in hand and digit lengths.

scholarly journals Differences in digit ratios between gay men who prefer receptive versus insertive sex roles indicate a role for prenatal androgen

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ashlyn Swift-Gallant ◽  
Victor Di Rita ◽  
Christina A. Major ◽  
Christopher J. Breedlove ◽  
Cynthia L. Jordan ◽  
...  
Keyword(s):  
Gay Men ◽  
Sex Role ◽  
Gender Nonconformity ◽  
Critical Periods ◽  
Same Sex ◽  
Digit Ratios ◽  
Right Hand ◽  
Prenatal Androgens ◽  
The Right ◽  
Prenatal Androgen

AbstractAmong non-human mammals, exposure to androgens during critical periods of development leads to gynephilia (attraction to females), whereas the absence or low levels of prenatal androgens leads to androphilia (attraction to males). However, in humans, retrospective markers of prenatal androgens have only been associated with gynephilia among women, but not with androphilia among men. Here, we asked whether an indirect indication of prenatal androgen exposure, 2D:4D, differs between subsets of gay men delineated by anal sex role (ASR). ASR was used as a proxy for subgroups because ASR groups tend to differ in other measures affected by brain sexual differentiation, such as gender conformity. First, we replicated the finding that gay men with a receptive ASR preference (bottoms) report greater gender nonconformity (GNC) compared to gay men with an insertive ASR preference (tops). We then found that Tops have a lower (male-typical) average right-hand digit ratio than Bottoms, and that among all gay men the right-hand 2D:4D correlated with GNC, indicating that a higher (female-typical) 2D:4D is associated with increased GNC. Differences were found between non-exclusive and exclusive same-sex attraction and GNC, and ASR group differences on digit ratios do not reach significance when all non-heterosexual men are included in the analyses, suggesting greater heterogeneity in the development of non-exclusive same-sex sexual orientations. Overall, results support a role for prenatal androgens, as approximated by digit ratios, in influencing the sexual orientation and GNC of a subset of gay men.

scholarly journals Radiological Analysis of Hind Paw Joint in Murine Rheumatoid Arthritis Model Treated Prophylactically Or Therapeutically with Cassia fistula versus Naproxen

2020 ◽  
Vol 34 (4) ◽  
pp. 58-63
Author(s):  
Hassan Farooq ◽  
Mariyam Iftikhar Piracha ◽  
Muhammad Usman ◽  
Rabia Tariq ◽  
Saadia Shahzad Alam
Keyword(s):  
Rheumatoid Arthritis ◽  
Complete Freund’S Adjuvant ◽  
Male Rats ◽  
X Rays ◽  
Cassia Fistula ◽  
Freund’S Adjuvant ◽  
Complete Freund's Adjuvant ◽  
Freund's Adjuvant ◽  
Animal House ◽  
Radiological Analysis

Introduction: Cassia fistula has anti-inflammatory activity. Rheumatoid arthritis (RA) is an autoimmune disease, causing inflammation and disability of the affected joints. It is mostly treated symptomatically with NSAIDs, which themselves have a lot of adverse effects. In this study the anti-arthritic effect of Cassia fistula versus naproxen has been observed radiologically. Aims & Objectives: The present study was radiological analysis of anti-arthritic effect of Cassia fistula compared to naproxen in Complete Freund’s Adjuvant (CFA) induced rat model of rheumatoid arthritis. Place and duration of study: This study was conducted at the Animal House of University of Veterinary and Animal Sciences, Lahore for a period of three months. Material & Methods: The study was carried out on 96 male rats divided into 12 groups of 8 rats each. Single 0.2ml dose of Complete Freund’s Adjuvant (CFA) was injected in the right hind paw of each rat in all groups except Group 1 (negative control). Group 2 was positive control. The prophylactic (3-7) and therapeutic (8- 12) groups were given naproxen (25mg/kg), anthraquinone extract (250 &500mg/kg) or methanolic extract (250 & 500mg/kg) of Cassia fistula orally BD on days 1,2 &3 (first dose preceding CFA injection by 30 minutes) and on days 9,10 &11 for therapeutic groups respectively. On day 15, x-rays of right ankle joints of all groups were taken as a confirmatory investigation on the final status of the arthritis. Results: Our results showed both anthraquinone and methanolic extracts of Cassia fistula have dose dependent (500˃250mg/dl) prophylactic and therapeutic anti-arthritic potential albeit lesser than naproxen 25mg/kg, to reduce the swelling of hind paw and deformity of interphalangeal joints on radiological examination. Conclusion: The efficacy of Cassia fistula makes it a potential weaker candidate to naproxen in prevention and treatment of rheumatoid arthritis.

EVIDENCE FOR ASSORTATIVE MATING ON DIGIT RATIO (2D:4D), A BIOMARKER FOR PRENATAL ANDROGEN EXPOSURE

2007 ◽  
Vol 39 (4) ◽  
pp. 599-612 ◽  
Author(s):  
MARTIN VORACEK ◽  
STEFAN G. DRESSLER ◽  
JOHN T. MANNING
Keyword(s):  
Assortative Mating ◽  
Age Differences ◽  
Research Programme ◽  
Digit Ratio ◽  
Left Hand ◽  
Right Hand ◽  
Androgen Exposure ◽  
The Right ◽  
Prenatal Androgen ◽  
Spousal Similarity

SummaryThe second-to-fourth digit ratio (2D:4D) presents an anatomical sex difference in humans. On average, men tend to have lower 2D:4D compared with women. There is fairly strong evidence for a role of the 2D:4D ratio as a biomarker for the organizational (permanent) effects of prenatal testosterone on the brain and behaviour. Recently, an accumulating research programme has shown 2D:4D to be related to a multitude of sex-dependent, hormonally influenced biosocial traits and phenotypes which reach into the domains of ability, behaviour, fertility, health, personality and sexuality. This study investigated the degree of assortative mating (spousal similarity) in a sample of 239 native Austrian couples of parental or grandparental age, all of them having reproduced. Results included: (i) significant spousal correlations of +0·19 and +0·18 for right-hand and left-hand 2D:4D, respectively, and +0·24 for average 2D:4D; (ii) no assortative mating effect on the right-minus-left difference in 2D:4D; (iii) indications consistent with a possible generational decrease of spousal similarity in 2D:4D; (iv) a prevalence of couples with a lower right-hand 2D:4D observed in the husband compared with his wife; and (v) relations of spousal 2D:4D patterns to spousal age differences, such that matings of men with more male-typical trait expressions (namely, a generally low right-hand 2D:4D or showing a lower right-minus-left 2D:4D difference than their wives) implicated larger male-minus-female age differences, i.e. younger wives. It is argued that assortative mating on 2D:4D operates indirectly and may be mediated through the assortment on other, more perceptible, physical traits and psychological phenotypes that entertain associations with 2D:4D and are relevant for courtship and mate choice.

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