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Özdemir Ç, Durmaz A. Association of second and fourth digit (2D:4D) ratios with metabolic syndrome and cardiovascular disease risk. Early Hum Dev 2024; 195:106078. [PMID: 39013212 DOI: 10.1016/j.earlhumdev.2024.106078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 07/10/2024] [Accepted: 07/10/2024] [Indexed: 07/18/2024]
Abstract
BACKGROUND The study aimed to investigate the association of second and fourth-digit (2D:4D) ratios with metabolic syndrome (MS) and cardiovascular disease risk (CVR). METHOD This case-control study was conducted between February and March 2024 with 200 participants (100 patients +100 controls). Biochemical parameters (glucose, total cholesterol, HDL, LDL, triglycerides, haemogram, HbA1C) were recorded. All participants were evaluated in terms of MS diagnostic criteria. CVR was calculated with the ESC CVD Risk Calculator. Second-digit and fourth-digit measurements were performed and the 2D:4D ratio of both hands and the difference between 2D:4D of both hands (Dr-l) were obtained. The relationship between 2D:4D and MS, CVR, and gender was evaluated. p < .05 was considered statistically significant. RESULTS Forty-one percent of the study participants were male. The right-hand 2D:4D (R2D:4D) ratio was 1.009 ± 0.04 and the left-hand 2D:4D (L2D:4D) ratio was 0.991 ± 0.04 (p < .001). R2D:4D ratio was 1.010 ± 0.04 in women and 0.985 ± 0.03 in men (p = .019). R2D:4D (p < .001), Dr-l (p = .001), and CVR (p < .001) were significantly higher in men with MS (+) compared to MS (-). CONCLUSION In our study, the R2D:4D ratio was found to be associated with MS and CVR in men. Low intrauterine androgen exposure may affect the development of MS, but this effect is more prominent in males.
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Affiliation(s)
- Çağla Özdemir
- Kütahya Health Sciences University, Evliya Çelebi Training and Research Hospital, Family Medicine Department, Kütahya, Turkey.
| | - Adem Durmaz
- Kütahya Health Sciences University, Evliya Çelebi Training and Research Hospital, Family Medicine Department, Kütahya, Turkey
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Sorokowski P, Kowal M. Relationship between the 2D:4D and prenatal testosterone, adult level testosterone, and testosterone change: Meta-analysis of 54 studies. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2024; 183:20-38. [PMID: 37795916 DOI: 10.1002/ajpa.24852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 08/29/2023] [Accepted: 09/12/2023] [Indexed: 10/06/2023]
Abstract
The ratio between the hands' second to the fourth finger (2D:4D) is commonly hypothesized to result from prenatal testosterone. The 2D:4D has also been hypothesized to relate to adult-level testosterone and, more recently, to the testosterone response to a challenging situation. In the present work, we tested these core assumptions. Drawing from, in total, 54 studies and 8077 participants, we investigated whether the 2D:4D is related to adult level testosterone (44 studies), testosterone change (6 studies), and prenatal testosterone (10 studies). We found no evidence of the relationship between the above testosterone types and digit ratios. Furthermore, there was no relationship between testosterone and the right and left 2D:4D, male and female 2D:4D, and the 2D:4D and testosterone measurement (i.e., measured in blood or saliva). However, we found some evidence that prenatal testosterone measured in amniotic fluid (but not cord blood) might be related to the digit ratios-further studies are necessary to validate this observation. In summary, considering the current state of knowledge, any conclusions drawn from the assumption of the digit ratios as the proxy for testosterone (prenatal, adult level, or testosterone change under a challenging situation) warrant great caution.
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Affiliation(s)
| | - Marta Kowal
- IDN Being Human Lab, University of Wrocław, Wrocław, Poland
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Butovskaya M, Adam Y, Batsevich V, Shackelford TK, Fink B. Direct and radiographic digit ratio (2D:4D) measurements of Tuvan children and adolescents from Southern Siberia: Sex differences and skeletal maturation. Early Hum Dev 2023; 184:105835. [PMID: 37517120 DOI: 10.1016/j.earlhumdev.2023.105835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 07/26/2023] [Accepted: 07/26/2023] [Indexed: 08/01/2023]
Abstract
BACKGROUND In Mongolian-origin ethnic groups digit ratio (2D:4D; a proxy for prenatal sex-steroids) is sexually dimorphic (males < females), as reported for other ethnicities. Most studies measured 2D:4D from soft tissue (directly from the digits, or indirectly from hand scans), or from radiographs. Evidence on the correspondence of 2D:4D measurements from soft tissue with measurements from radiographic images is scarce and has not been reported for a Mongolian-origin sample. In addition, previous research has not considered relationships between 2D:4D and measures of skeletal maturity. AIM To examine (i) associations between 2D:4D measured directly from the palms with those obtained from radiographic images of the same individuals in a sample of children and adolescents from the Tuvan population in Siberia (Russian Federation), and ii) associations between 2D:4D measurements with chronological and skeletal age. SUBJECTS AND METHODS Participants were Tuvan boys and girls aged 7 to 18 years. 2D:4D of the right and left hand was measured from soft tissue (directly from the palm) and compared with radiographic images (left hand only). In addition to finger length 2D:4D, we examined 2D:4D of the phalanges from measurements of radiographs. Skeletal age was assessed using the Tanner-Whitehouse method. RESULTS Sex differences (boys < girls) in measurements of 2D:4D from soft tissue and radiographs were found for total finger length and phalanges. In addition, 2D:4D measurements from radiographs correlated positively and significantly with those obtained from soft tissue. Sex predicted 2D:4D measurements from soft tissue and radiographs, but no effects of chronological/skeletal age and body height were detected. In girls (but not in boys), earlier skeletal maturity (relative to chronological age) was associated with higher 2D:4D in soft tissue measurements of both hands, radiographic 2D:4D, and 2D:4D of the proximal phalanges. CONCLUSION Consistent with reports from other ethnic groups, 2D:4D in young Tuvans was sexually dimorphic, with boys having lower 2D:4D than girls. For girls, higher 2D:4D was found for participants whose skeletal age was more advanced than chronological age. This finding was obtained from direct soft tissue and indirect radiographic measurements. Age and body height were not associated with 2D:4D, which suggests differences in hormone developmental trajectories for 2D:4D and height.
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Affiliation(s)
- Marina Butovskaya
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Moscow, Russian Federation; National Research University Higher School of Economics, Moscow, Russian Federation; Russian State University for the Humanities, Moscow, Russian Federation
| | - Yulia Adam
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Moscow, Russian Federation
| | - Valery Batsevich
- Anuchin Research Institute and Museum of Anthropology, Lomonosov Moscow State University, Moscow, Russian Federation
| | | | - Bernhard Fink
- Department of Evolutionary Anthropology, University of Vienna, Vienna, Austria; Human Evolution and Archaeological Sciences (HEAS), University of Vienna, Vienna, Austria; Biosocial Science Information, Biedermannsdorf, Austria.
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Evcen R, Çölkesen F, Saygın DA, Aykan FS, Kılınç M, Ergün ÜY, Akkuş FA, Önalan T, Yıldız E, Arslan Ş. High digit ratio (2D:4D) is associated with attack frequency and severity in hereditary angioedema patients. Early Hum Dev 2023; 177-178:105724. [PMID: 36827749 DOI: 10.1016/j.earlhumdev.2023.105724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/03/2023] [Accepted: 02/03/2023] [Indexed: 02/11/2023]
Abstract
BACKGROUND Hereditary angioedema (HAE) caused by a deficiency or dysfunction of the plasma protease C1-inhibitor is a rare autosomal-dominant disorder. We explored a possible correlation between the ratio of the second and fourth finger lengths (2D:4D) and the frequency of HEA attacks, and whether the ratio might predict laryngeal attack. METHOD We evaluated 35 HEA patients aged 19 to 66 years; 3 were subsequently excluded. The 2D:4D ratio was calculated by dividing the length of the second finger by that of the fourth finger of both hands. A structured clinical questionnaire exploring HAE course and treatment over the prior year was administered. RESULTS Of the 32 participants, 56.25 % (n = 18) were female. Of them, those with high 2D:4D ratios suffered significantly more laryngeal attacks than others; 93.3% of patients with high 2D:4D ratios experienced ≥5 attacks annually, significantly more than those with low ratios. Among type 2 HEA patients, 75 % of those experiencing ≥5 attacks annually had high 2D:4D ratios; all patients with low 2D:4D ratios reported <5 attacks annually. These significant effects were found for right-hand 2D:4D ratios and not left-hand 2D:4D ratios. CONCLUSION The data suggest that intrauterine sex hormone exposure, which affects the 2D:4D ratio, is significantly associated with HEA attack frequency and severity, and laryngeal edema.
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Affiliation(s)
- Recep Evcen
- Division of Clinical Immunology and Allergy, Department of Internal Medicine, Necmettin Erbakan University, Meram Faculty of Medicine, Konya, Turkey.
| | - Fatih Çölkesen
- Division of Clinical Immunology and Allergy, Department of Internal Medicine, Necmettin Erbakan University, Meram Faculty of Medicine, Konya, Turkey
| | - Duygu Akın Saygın
- Department of Anatomy, Necmettin Erbakan University, Meram Faculty of Medicine, Konya, Turkey
| | - Filiz Sadi Aykan
- Division of Clinical Immunology and Allergy, Department of Internal Medicine, Necmettin Erbakan University, Meram Faculty of Medicine, Konya, Turkey
| | - Mehmet Kılınç
- Division of Clinical Immunology and Allergy, Department of Internal Medicine, Necmettin Erbakan University, Meram Faculty of Medicine, Konya, Turkey
| | - Ümmügülsüm Yılmaz Ergün
- Division of Clinical Immunology and Allergy, Department of Internal Medicine, Necmettin Erbakan University, Meram Faculty of Medicine, Konya, Turkey
| | - Fatma Arzu Akkuş
- Division of Clinical Immunology and Allergy, Department of Internal Medicine, Necmettin Erbakan University, Meram Faculty of Medicine, Konya, Turkey
| | - Tuğba Önalan
- Division of Clinical Immunology and Allergy, Department of Internal Medicine, Necmettin Erbakan University, Meram Faculty of Medicine, Konya, Turkey
| | - Eray Yıldız
- Necip Fazıl City Hospital, Division of Clinical Immunology and Allergy, Kahramanmaraş, Turkey
| | - Şevket Arslan
- Division of Clinical Immunology and Allergy, Department of Internal Medicine, Necmettin Erbakan University, Meram Faculty of Medicine, Konya, Turkey
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Uchida M, Iwamoto T, Yamasaki K, Kariya F, Konishi S. The ratio of 2nd to 4th digit length and reproductive function of infertile male patients. Reprod Med Biol 2023; 22:e12500. [PMID: 36789270 PMCID: PMC9909166 DOI: 10.1002/rmb2.12500] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 12/02/2022] [Accepted: 12/26/2022] [Indexed: 02/11/2023] Open
Abstract
Purpose To investigate the relationship between the ratio of index to ring finger lengths (2D:4D ratio), reflecting androgen exposure in utero, and reproductive function among men. Methods Male patients (N = 180) who consulted for fertility issues participated in the study. The palms of both hands were scanned, and the 2D:4D ratio was calculated. Data on semen volume, sperm concentration and total motility, total and motile sperm counts, and serum hormone concentrations were obtained. Spearman correlation coefficients between the 2D:4D ratio and hormone and semen quality parameters were calculated. Results The total sperm count was significantly negatively correlated with the 2D:4D ratio of the left hand (r = -0.154, p = 0.039) but not with that of the right hand (r = -0.045, p = 0.548). Testosterone showed weak negative correlations with the 2D:4D ratio in the left (r = -0.142, p = 0.058) and right (r = - 0.149, p = 0.046) hands. Follicle-stimulating hormone levels were negatively correlated with the 2D:4D ratios of the left (r = -0.173, p = 0.020) and right (r = -0.164, p = 0.027) hands. Other semen quality parameters or luteinizing hormone levels showed no significant correlation with the 2D:4D ratios. Conclusions No clear associations were observed between the 2D:4D ratios and reproductive function.
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Affiliation(s)
| | - Teruaki Iwamoto
- International University of Health and WelfareOtawaraTochigiJapan,Sanno HospitalMinatoTokyoJapan
| | - Kazumitsu Yamasaki
- Tsukuba Gakuen HospitalIbarakiTsukubaJapan,Sanno HospitalMinatoTokyoJapan
| | - Fumiko Kariya
- Department of Human Ecology, School of International Health, Graduate School of MedicineThe University of TokyoBunkyoTokyoJapan
| | - Shoko Konishi
- Department of Human Ecology, School of International Health, Graduate School of MedicineThe University of TokyoBunkyoTokyoJapan
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Banyeh M, Appiah SK, Abubakari A, Issah M, Amidu N. Sex-moderated relationship between the 2D:4D ratio and circulating hormones in an adult Ghanaian population. Physiol Rep 2023; 11:e15578. [PMID: 36695786 PMCID: PMC9875815 DOI: 10.14814/phy2.15578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 01/02/2023] [Accepted: 01/03/2023] [Indexed: 06/17/2023] Open
Abstract
The second-to-fourth digit ratio (2D:4D) is the putative marker of prenatal hormone exposure. The 2D:4D ratio or the right-left difference (Dr-l) are said to be negative and positive correlates, respectively, of circulating testosterone and estrogen in both adult males and females. However, previous studies on the subject have reported mixed results. This study aimed to determine the sex-moderated relationship between the 2D:4D ratio and adult circulating testosterone, estradiol, testosterone-to-estradiol ratio and the free androgen index. This was a cross-sectional study from January to June 2021 at the University for Development Studies, Ghana. The study involved 62 participants (Female = 28; Male = 34), aged between 20 and 26 years. The right (2D:4DR), the left (2D:4DL), and their difference (Dr-l) were measured by computer-assisted analysis. Fasting venous samples were assayed for total testosterone (T), estradiol (E2 ), and sex hormone-binding globulin (SHBG) using ELISA. The free androgen index (FAI) was then calculated (T/SHBG) and the data were analyzed using moderated and/or weighted regression. Males had significantly higher T and FAI than females while females had significantly higher E2 than males, which were independent of age and body mass index (p < 0.001). There was a significant SEX*Dr-l interaction on FAI (p = 0.007). The Dr-l correlated negatively with FAI in males but positively in females and accounted for about 94.0% of the variability of FAI in males (adjR2 = 0.940) and only 0.2% in females (adjR2 = 0.002). The 2D:4D ratio, a putative marker of prenatal hormone exposure, may have an impact on sex differences in adult free androgen index.
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Affiliation(s)
- Moses Banyeh
- Department of Biomedical Laboratory ScienceUniversity for Development StudiesTamaleGhana
| | - Samuel Kwasi Appiah
- Department of Biomedical Laboratory ScienceUniversity for Development StudiesTamaleGhana
| | - Abdul‐Malawi Abubakari
- Department of Biomedical Laboratory ScienceUniversity for Development StudiesTamaleGhana
| | - Musah Issah
- Department of Biomedical Laboratory ScienceUniversity for Development StudiesTamaleGhana
| | - Nafiu Amidu
- Department of Biomedical Laboratory ScienceUniversity for Development StudiesTamaleGhana
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Kumar S, Voracek M. Effects of caste, birth season, and family income on digit ratios. Am J Hum Biol 2022; 35:e23852. [PMID: 36524699 DOI: 10.1002/ajhb.23852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 12/05/2022] [Accepted: 12/06/2022] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVES The contributions of latitude and ethnicity in the determination of cross-society differences in digit ratios are unclear. In India, different castes (endogamous groups) have been living in the same areas (villages or towns) for the last 1500 years and, therefore, these groups may have different gene pools without a latitude-related difference component. Thus, in the present study, we studied the effect of caste on digit ratios. We also studied the effects of sex, birth season, and family income on digit ratios. METHODS We selected a sample of 301 college students (age: M = 19.9 years, SD = 2.63) in Muzaffarnagar city of western Uttar Pradesh, India, and asked participants for information regarding their birth month, religion, caste, and monthly family income. We measured participants' dorsal and palmar digit lengths (of all fingers, except the thumb, in both hands) using vernier calipers of 0.01 mm accuracy. RESULTS Other backward castes (intermediate castes) had longer digit lengths than general castes (upper castes), scheduled castes (lower castes), and Muslims. However, there was no difference in digit ratios of caste groups (scheduled castes vs. other backward castes vs. general castes vs. Muslims) or specific castes (Chamar-Jatav vs. Jat vs. Pandit-Tyagi). Winter-born women had lower left dorsal 2D:4D and 3D:4D ratios than summer-born women. Family income was related to higher dorsal 2D:4D and 3D:4D ratios among women. Moreover, in dorsal digit ratios, sex difference (men < women) occurred in digit ratios constituting digit 5, whereas, in palmar digit ratios, sex difference occurred in digit ratios constituting digit 2. CONCLUSIONS The present study suggests that endogamy-led genetic difference in ethnic/caste groups is not a determinant, whereas birth season (i.e., the exposure to sunlight) and family income might be determinants of digit ratios. In addition, compared to palmar digit ratios, dorsal digit ratios are better markers of sexual dimorphism.
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Affiliation(s)
- Sanjay Kumar
- Department of Psychology D.A.V. College Muzaffarnagar Uttar Pradesh India
| | - Martin Voracek
- Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology University of Vienna Vienna Austria
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Finley B, Kalwij A, Kapteyn A. Born to be wild: Second-to-fourth digit length ratio and risk preferences. ECONOMICS AND HUMAN BIOLOGY 2022; 47:101178. [PMID: 36084390 DOI: 10.1016/j.ehb.2022.101178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 07/20/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
The second-to-fourth digit length ratio of an individual's hand (digit ratio) is a putative biomarker for prenatal exposure to testosterone. We examine the hypothesized negative association between the digit ratio and the preference for risk taking within a large U.S. population survey. Our statistical framework provides a cardinal proxy for the true digit ratio based on ordinal digit ratio measurements and accounts for measurement error under the assumptions of Gaussianity and time-invariant true digit ratios. Our empirical findings support the hypothesis and suggest a meaningful biological basis for risk preferences.
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Affiliation(s)
| | - Adriaan Kalwij
- Utrecht University School of Economics, The Netherlands.
| | - Arie Kapteyn
- Center for Economic and Social Research at the University of Southern California, United States.
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Banyeh M, Zogli KE, Osumanu HA, Obeng L, Acheampong TK, Dagungong CB, Bayor E, Amidu N. Does sex interact with the 2D:4D ratio or adult circulating hormones on the estimated glomerular filtration rate? A cross-sectional study in Ghana. Physiol Rep 2022; 10:e15516. [PMID: 36385503 PMCID: PMC9669620 DOI: 10.14814/phy2.15516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 10/28/2022] [Accepted: 10/29/2022] [Indexed: 06/16/2023] Open
Abstract
The 2D:4D ratio is the putative marker of prenatal hormone exposure and has been suggested as a correlate of adult circulating testosterone and estrogen. The study aimed to determine whether sexual dimorphism in the estimated glomerular filtration rate (eGFR) can be partly explained by the 2D:4D ratio or adult circulating testosterone or estrogen. The study was cross-sectional from June to December 2021 at the University for Development Studies. The study involved 206 healthy adults (Female = 93, Male = 113) between 18 and 30 years. The 2D:4D ratio was measured using computer-assisted analysis. Venous blood samples were collected and analyzed for testosterone, estradiol and creatinine using the ELISA technique and routine biochemical analysis. The adjusted eGFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine equation (2021). The eGFR and the testosterone-to-estradiol ratio (TT:E2 ) were significantly higher in males than in females (p < 0.001). There was a significant interaction between sex and the TT:E2 on the eGFR (p < 0.001). Although the relationship between the eGFR and the TT:E2 was negative in both males and females, a unit change in the TT:E2 had a greater impact on the eGFR in females (B = -1.38) than in males (B = -0.01). Sexual dimorphism in the eGFR is influenced by both testosterone and estradiol. Although the sex difference in the eGFR may be influenced by the TT:E2 , estrogen seems to account for more variability in the eGFR than testosterone.
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Affiliation(s)
- Moses Banyeh
- Department of Biomedical Laboratory ScienceUniversity for Development StudiesTamaleGhana
| | - Kervin Edinam Zogli
- Department of Biomedical Laboratory ScienceUniversity for Development StudiesTamaleGhana
| | | | - Lawrence Obeng
- Department of Biomedical Laboratory ScienceUniversity for Development StudiesTamaleGhana
| | | | | | - Elizabeth Bayor
- Department of Biomedical Laboratory ScienceUniversity for Development StudiesTamaleGhana
| | - Nafiu Amidu
- Department of Biomedical Laboratory ScienceUniversity for Development StudiesTamaleGhana
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Jägetoft Z, Unenge Hallerbäck M, Julin M, Bornehag CG, Wikström S. Anthropometric measures do not explain the 2D:4D ratio sexual dimorphism in 7-year-old children. Am J Hum Biol 2022; 34:e23776. [PMID: 35751545 PMCID: PMC9540332 DOI: 10.1002/ajhb.23776] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/13/2022] [Accepted: 06/14/2022] [Indexed: 12/05/2022] Open
Abstract
Objectives Digit ratio (2D:4D) might reflect prenatal testosterone exposure and has been used as a putative marker for androgen related outcomes. However, such associations might be inflicted by confounders. Application of 2D:4D in epidemiological research motivate identification of biological background determinants. We examined sex, anthropometric measures, and maternal factors as determinants of 2D:4D in Swedish 7‐year‐old children. Methods The study was embedded in the Swedish Environmental, Longitudinal, Mother and Child, Asthma and Allergy (SELMA) pregnancy cohort. A total of 870 pre‐pubertal children, median 7.5 years of age, were studied. A single assessor performed digit measurements from scanned photocopies using computer software. Child anthropometric measurements investigated were hand size, birthweight, recumbent birth length, standing height, weight, BMI, body fat percentage, and waist/hip circumference. Maternal factors included age, pregnancy length, parity, and education. Results We found a significant sexual dimorphism regarding digit lengths and 2D:4D, boys on average presenting a lower 2D:4D than girls also after adjustment for summed finger lengths and body fatness. In crude analyses, maternal age correlated with 2D:4D across the whole population and in females but not in adjusted models. No other study variables were associated with 2D:4D. Conclusion Digit ratio showed sexual dimorphism at the age of seven and seems to represent a true sex difference rather than an artifact and bias from hand size, body size or body fat content. Among the rest of our investigated variables, we found no determinants constituting important confounders in future research on 2D:4D ratio.
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Affiliation(s)
- Zebulohn Jägetoft
- Centre for Research and Education, County Council of Värmland, Karlstad, Sweden
| | - Maria Unenge Hallerbäck
- Centre for Research and Education, County Council of Värmland, Karlstad, Sweden.,Department of Health Sciences, Karlstad University, Karlstad, Sweden.,School of Medical Science, Örebro University, Örebro, Sweden
| | - Maria Julin
- Västerås Hospital, County Council of Västmanland, Västerås, Sweden
| | - Carl-Gustaf Bornehag
- Department of Health Sciences, Karlstad University, Karlstad, Sweden.,Department of Preventive Medicine, Ichan School of Medicine at Mount Sinai, New York, New York, USA
| | - Sverre Wikström
- Centre for Research and Education, County Council of Värmland, Karlstad, Sweden.,Department of Health Sciences, Karlstad University, Karlstad, Sweden.,School of Medical Science, Örebro University, Örebro, Sweden
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Otterbring T, Elbæk CT, Lu C. Can Digit Ratio and Gender Identity Predict Preferences for Consumption Options With a Distinct Gender Image? Front Psychol 2022; 13:923709. [PMID: 35756313 PMCID: PMC9220292 DOI: 10.3389/fpsyg.2022.923709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 05/11/2022] [Indexed: 11/16/2022] Open
Abstract
This study investigated whether individuals' preferences for masculine (vs. feminine) consumption options could be predicted by a biological sex cue (the 2D:4D digit ratio; a biomarker linked to prenatal testosterone exposure), and a psychological gender cue (self-perceived gender identity). Chinese participants (N = 216) indicated their preferences for a series of binary options that differed in their perceived gender image (e.g., romantic comedy vs. action thriller; pop music vs. hard rock), with one of the options evaluated as relatively more feminine and the other viewed as comparably more masculine. Participants also self-reported their gender identity and the length of their index and ring fingers, which was used to calculate their 2D:4D digit ratios. A low (male-typical) digit ratio and a masculine gender identity were both associated with more masculine preferences, regardless of participants' biological sex. However, a low digit ratio predicted preferences for masculine consumption options only in female participants with a masculine gender identity, but not in those with a feminine gender identity. These findings add to the literature on whether and when biological sex cues and psychological gender cues can predict preferences for options with a distinct gender image and suggest that the connection between these cues is more complex in women than in men.
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Affiliation(s)
- Tobias Otterbring
- Department of Management, School of Business and Law, University of Agder, Kristiansand, Norway
- Institute of Retail Economics, Stockholm, Sweden
| | | | - Chaoren Lu
- Kunming Academy of Governance, Kunming, China
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12
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Iljin A, Antoszewski B, Szewczyk T, Sitek A. The 2D:4D index is associated with the development of excess body weight in adults, but not with the rate of weight loss following bariatric surgery. Sci Rep 2022; 12:8078. [PMID: 35578001 PMCID: PMC9110364 DOI: 10.1038/s41598-022-12306-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 05/09/2022] [Indexed: 01/17/2023] Open
Abstract
2D:4D finger length ratio is a proxy of prenatal sex hormone exposure. Prenatal testosterone decreases and prenatal estrogens increase this index. In the current study we investigated whether the 2D:4D index, as a marker of the prenatal hormonal environment, is associated with the development of overweight and obesity in adults, and whether is it correlated with the rate of weight loss in patients after bariatric surgery. We tested 125 adults with obesity (BMI ≥ 30.0 kg/m2), 125 adults with overweight (BMI 25.0–29.9 kg/m2) and 153 persons with normal body weight (BMI < 25 kg/m2) of both sexes. We have found that the development of excessive body weight in men and women, and fat accumulation in the upper arms, thighs and lower legs in women with obesity (but not men) are associated with increased prenatal estrogen exposure. This relationship indicates a new area of activity in the field of obesity prevention. Moreover, it seems that the 2D:4D index (especially of the right hand) may be a useful factor in early prediction of the risk of developing excessive body weight in humans. The rate of weight loss after bariatric surgery is independent of prenatal exposure to sex hormones.
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Affiliation(s)
- Aleksandra Iljin
- Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Lodz, ul. Kopcińskiego 22, 90-153, Łódź, Poland
| | - Bogusław Antoszewski
- Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Lodz, ul. Kopcińskiego 22, 90-153, Łódź, Poland
| | - Tomasz Szewczyk
- Clinical Department of Gastroenterology, Oncology and General Surgery, USK No. 1, ul. Kopcińskiego 22, 90-153, Łódź, Poland.,Department of General Surgery, Regional Health Center, ul. Gen. Józefa Bema 5-6, 59-300, Lubin, Poland
| | - Aneta Sitek
- Department of Anthropology, Faculty of Biology and Environmental Protection, University of Lodz, ul. Banacha 12/16, 90-237, Łódź, Poland.
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Banyeh M, Amidu N. The association between the 2D:4D ratio and offspring sex at birth: A cross-sectional study in Ghana. Am J Hum Biol 2022; 34:e23744. [PMID: 35266228 DOI: 10.1002/ajhb.23744] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 11/07/2022] Open
Abstract
OBJECTIVES The 2D:4D ratio is the putative marker of prenatal androgen exposure. Low maternal 2D:4D ratio has been associated with high or male-biased secondary sex ratio. Hitherto, there has not been any study in Ghana regarding the maternal 2D:4D ratio and sex ratio at birth. This study sought to investigate this observation in a Ghanaian population. METHOD The study was cross-sectional from December 2020 to April 2021 involving 272 first-time mothers. The mean ± SD age of the mothers was 23.9 ± 3.67 years. The right (2D:4DR), the left (2D:4DL), the mean (M2D:4D) digit ratios and the right-left difference (Dr-l) of the mothers were measured using computer-assisted analysis. The mothers were stratified by their digit ratios, and the cohort sex ratio (CSR) for each stratum was then calculated as the proportion of sons. RESULTS The mean ± SD of the 2D:4DR of mothers-with-daughters and mothers-with-sons were 0.941 ± 0.032 and 0.933 ± 0.037, respectively. The mean ± SD of the 2D:4DL of mothers-with-daughters was 0.934 ± 0.034, while that of mothers-with-sons was 0.931 ± 0.039. The offspring sex at birth and the CSR was not associated with either the mother's right, left, mean 2D:4D ratio or their difference (Dr-l). However, mothers-with-daughters showed rightward asymmetry in their 2D:4D ratios as the Dr-l significantly and positively deviated from zero (p < .010). CONCLUSION The maternal 2D:4D ratio may not be associated with their offspring sex at birth among first-time mothers. This study adds to the limited data on studies regarding offspring sex at birth and the 2D:4D ratio in Ghana and Sub-Saharan Africa.
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Affiliation(s)
- Moses Banyeh
- Department of Biomedical Laboratory Science, School of Allied Health Sciences, University for Development Studies, Tamale, Ghana
| | - Nafiu Amidu
- Department of Biomedical Laboratory Science, School of Allied Health Sciences, University for Development Studies, Tamale, Ghana
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Lidborg LH, Cross CP, Boothroyd LG. A meta-analysis of the association between male dimorphism and fitness outcomes in humans. eLife 2022; 11:e65031. [PMID: 35179485 PMCID: PMC9106334 DOI: 10.7554/elife.65031] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 02/17/2022] [Indexed: 11/13/2022] Open
Abstract
Humans are sexually dimorphic: men and women differ in body build and composition, craniofacial structure, and voice pitch, likely mediated in part by developmental testosterone. Sexual selection hypotheses posit that, ancestrally, more 'masculine' men may have acquired more mates and/or sired more viable offspring. Thus far, however, evidence for either association is unclear. Here, we meta-analyze the relationships between six masculine traits and mating/reproductive outcomes (96 studies, 474 effects, N = 177,044). Voice pitch, height, and testosterone all predicted mating; however, strength/muscularity was the strongest and only consistent predictor of both mating and reproduction. Facial masculinity and digit ratios did not significantly predict either. There was no clear evidence for any effects of masculinity on offspring viability. Our findings support arguments that strength/muscularity may be sexually selected in humans, but cast doubt regarding selection for other forms of masculinity and highlight the need to increase tests of evolutionary hypotheses outside of industrialized populations.
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Affiliation(s)
- Linda H Lidborg
- Department of Psychology, Durham UniversityDurhamUnited Kingdom
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15
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An Investigation of the Relationship Between the Second-to-Fourth Digit Ratio and Sagittal Synostosis. J Craniofac Surg 2022; 33:1705-1708. [PMID: 35148529 DOI: 10.1097/scs.0000000000008512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 01/11/2022] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND The most common presentation of nonsyndromic craniosynostosis is that of the sagittal suture. Amongst this subgroup there is a significant male preponderance. Although the etiology is largely unknown, androgen exposure in utero has been suggested as a contributing factor. The second-to-fourth digit ratio (2D:4D) is a sexually dimorphic trait, reflective of the levels of androgen and estrogen exposure in utero, with a lower 2D:4D ratio associated with higher androgen exposure.This study aimed to examine the difference in 2D:4D ratio between participants with sagittal synostosis (SS) and gender-matched controls, hypothesizing that alterations in androgen exposure would be reflected in participants' 2D:4D ratio. METHOD Participants with nonsyndromic SS and gender-matched controls were prospectively recruited from outpatients clinics. Photographs were taken of the right hand, and 3 independent researchers measured the length of the fingers and 2D:4D ratio, with the mean 2D:4D ratio then calculated. RESULTS Fifty-six participants were recruited to both groups, with 35 males and 21 females in each. The mean age of the study and control groups were 5.6 and 6.3 years, respectively. There was no difference in the 2D:4D ratio between groups overall (P = 0.126). However, males with SS had a significantly higher 2D:4D ratio in comparison to male controls (0.969 ± 0.379 versus 0.950 ± 0.354, P = 0.038). CONCLUSIONS Our results suggest that 1 single hormonal pathway is not responsible for suture fusion. Subsequently we consider that an imbalance between testosterone and estrogen signaling may contribute to the development of sagittal craniosynostosis.
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Short-term and long-term mate preference in men and women in an Iranian population. Sci Rep 2021; 11:20752. [PMID: 34675342 PMCID: PMC8531382 DOI: 10.1038/s41598-021-99653-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 09/24/2021] [Indexed: 11/11/2022] Open
Abstract
Mate preference in short-term relationships and long-term ones may depend on many physical, psychological, and socio-cultural factors. In this study, 178 students (81 females) in sports and 153 engineering students (64 females) answered the systemizing quotient (SQ) and empathizing quotient (EQ) questionnaires and had their digit ratio measured. They rated their preferred mate on 12 black-line drawing body figures varying in body mass index (BMI) and waist to hip ratio (WHR) for short-term and long-term relationships. Men relative to women preferred lower WHR and BMI for mate selection for both short-term and long-term relationships. BMI and WHR preference in men is independent of each other, but has a negative correlation in women. For men, digit ratio was inversely associated with BMI (p = 0.039, B = − 0.154) preference in a short-term relationship, and EQ was inversely associated with WHR preference in a long-term relationship (p = 0.045, B = − 0.164). Furthermore, men and women in sports, compared to engineering students, preferred higher (p = 0.009, B = 0.201) and lower BMI (p = 0.034, B = − 0.182) for short-term relationships, respectively. Women were more consistent in their preferences for short-term and long-term relationships relative to men. Both biological factors and social/experiential factors contribute to mate preferences in men while in women, mostly social/experiential factors contribute to them.
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Association of prenatal sex steroid exposure estimated by the digit ratio (2D:4D) with birth weight, BMI and muscle strength in 6- to 13-year-old Polish children. PLoS One 2021; 16:e0258179. [PMID: 34606496 PMCID: PMC8489707 DOI: 10.1371/journal.pone.0258179] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 09/22/2021] [Indexed: 11/30/2022] Open
Abstract
Objectives The aim of this paper was to provide evidence for the impact of prenatal sex steroid exposure on prenatal and postnatal body size parameters, and muscle strength in children. Methods The following anthropometric data were studied in a group of 1148 children (536 boys and 612 girls) aged 6–13 years: the 2D:4D digit ratio, birth weight and length, and birth head and chest circumference. Postnatal parameters (6–13 years) included body weight and height, BMI, waist and hip circumference, WHR, as well as grip strength in both hands. All parameters that required it were adjusted for sex and gestational or chronological age. A general linear model, Pearson’s correlation, t-statistics and Cohen’s Δ were used in statistical analysis. Results Among birth size parameters, only birth weight was significantly negatively correlated with the 2D:4D digit ratio in children. Higher (feminized) digit ratios were significantly correlated with postnatal parameters such as body weight, BMI, and waist and hip circumference (positively), as well as hand grip strength–a proxy for muscular strength (negatively). Conclusion Problems with maintaining adequate body size parameters and muscle strength may be programmed in fetal life and predicted on the basis of the 2D:4D digit ratio. Body weight at birth and in early ontogenesis are additive correlates of the 2D:4D ratio. The present findings suggest that the 2D:4D digit ratio is related to postnatal phenotypes such as birth weight, overweight, and obesity as well as muscle strength in 6–13-year-old children of both sexes.
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Richards G, Medland SE, Beaton AA. Digit ratio (2D:4D) and handedness: A meta-analysis of the available literature. Laterality 2021; 26:421-484. [PMID: 33517845 DOI: 10.1080/1357650x.2020.1862141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The Geschwind-Behan-Galaburda and sexual differentiation models predict an association between elevated foetal androgen exposure and left-handedness whereas the callosal hypothesis predicts the opposite. We present a meta-analysis of correlations between handedness and digit ratio (2D:4D), a putative marker of prenatal testosterone. Left-handedness predicted low (male-typical) right-hand digit ratio (R2D:4D), high (female-typical) left-hand digit ratio (L2D:4D), and low R2D:4D-L2D:4D directional asymmetry (D[R-L]). Effect sizes were extremely small and not moderated by sex or method of measuring handedness or 2D:4D. The same general pattern was observed after excluding the very large study (110,329 males, 90,412 females) of Manning and Peters ([2009]. Digit ratio (2D:4D) and hand preference for writing in the BBC Internet Study. Laterality: Asymmetries of Body, Brain and Cognition, 14(5), 528-540. doi:10.1080/13576500802637872); however, no significant effects for R2D:4D were observed once these samples were removed. The results do not confirm any theory linking prenatal androgens with handedness, so we speculate they instead reflect the mechanical action of writing causing subtle changes in the musculature and/or fat pads of the fingers. Gripping a pen/pencil might cause an increase in 2D relative to 4D (and/or decrease in 4D relative to 2D) resulting in higher ratios on the writing-hand; furthermore, this could differ between left- and right-handers due to writing in the left-to-right direction (as in English) having asymmetrical effects depending on which hand is used.
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Affiliation(s)
- Gareth Richards
- School of Psychology, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.,Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge, UK.,Centre for Research on Play in Education, Development & Learning, Faculty of Education, University of Cambridge, Cambridge, UK
| | - Sarah E Medland
- Psychiatric Genetics, QIMR Berghofer Medical Research Institute, Brisbane, Australia.,School of Psychology, University of Queensland, St Lucia, Australia.,School of Psychology and Counselling, Queensland University of Technology, Brisbane, Australia
| | - Alan A Beaton
- Department of Psychology, School of Human & Health Sciences, Swansea University, Swansea, UK.,Department of Psychology, Aberystwyth University, Aberystwyth, UK
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Association patterns between 2D:4D ratio and age at menarche: the impact of methodology. ANTHROPOLOGICAL REVIEW 2020. [DOI: 10.2478/anre-2020-0026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
The ratio of index finger to ring finger length (2D:4D) is a sexually dimorphic feature and widely used as an indicator of prenatal androgen-estrogen exposure. Several studies have investigated the relationship between the 2D:4D ratio and the onset of the first menstrual period (menarche) in women.
The present study tested the association patterns between 2D:4D ratio and age at menarche. Furthermore, the impact of methods of measuring finger lengths was considered.
Two samples were used to conduct the study. One sample consisted of 110 women who self-measured their finger lengths. The finger length measurements in the second sample (88 women) were taken from one trained observer using the caliper-based technique. Age at menarche was determined using a retrospective method.
Women from the first sample reported an average age for the onset of the first menstrual bleeding at 12.9 (SD = 1.4) years of age. There was no significant association between the left and right 2D:4D ratio and the age at menarche. The second sample showed a mean age at menarche at 12.8 (SD = 1.3) years of age. Here, the right hand 2D:4D ratio and age at menarche were significantly correlated (p<0.001).
A more feminine 2D:4D ratio was significantly associated with an earlier menarcheal age only in the sample with direct finger length measurements by a trained investigator. The sample using self-measurements yielded no significant associations between menarcheal age and 2D:4D. The use of a reliable and well-founded methodology is essential for obtaining meaningful results.
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20
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Effects of hand preference on digit lengths and digit ratios among children and adults. Early Hum Dev 2020; 151:105204. [PMID: 33059164 DOI: 10.1016/j.earlhumdev.2020.105204] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 09/28/2020] [Accepted: 09/29/2020] [Indexed: 01/21/2023]
Abstract
BACKGROUND Prenatal sex hormones may not exclusively determine effects of hand preference on digit ratios. Genetic determination is an alternative possibility. AIM To study the likelihood of similar effects of hand preference on digit lengths and digit ratios. METHODS We selected similar numbers of left-handers and right-handers in samples of kindergarten children (N = 101, age range: 3.5-7 years) and adults (N = 189, age range: 17-28 years) and measured digit lengths (excluding the thumb) directly on the palmar hand. RESULTS Compared to right-handers, left-handers had longer digits and lower third-to-fourth (3D:4D) digit ratios among children, whereas an opposite pattern of handedness differences occurred among adults. CONCLUSIONS Effects of hand preference on digit lengths and ratios might be genetically/ontogenetically determined. Also discussed are implications of this set of findings for digit ratio research.
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Richards G, Baron-Cohen S, van Steen T, Galvin J. Assortative mating and digit ratio (2D:4D): A pre-registered empirical study and meta-analysis. Early Hum Dev 2020; 151:105159. [PMID: 32942249 DOI: 10.1016/j.earlhumdev.2020.105159] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/10/2020] [Accepted: 08/18/2020] [Indexed: 02/06/2023]
Abstract
BACKGROUND It has been hypothesised that the ratio of length between the second and fourth fingers (2D:4D), commonly employed as an indicator of foetal sex hormone exposure, may be positively correlated between heterosexual partners. AIMS As previous evidence has been conflicting, our study aimed to determine whether intra-couple correlations exist for digit ratio variables, and if so, to estimate the size and direction of these effects. STUDY DESIGN We present a preregistered (osf.io/6jg8p) correlational study and quantitative meta-analysis of the available literature, and attempted to locate further published and unpublished data (i.e. 'grey literature') by contacting n = 248 researchers in the 2D:4D and related fields. SUBJECTS n = 58 heterosexual dating couples from the UK took part in our empirical study, and the meta-analysis included data from k = 11 samples. OUTCOME MEASURES We measured digit ratio for the right hand (R2D:4D), left hand (L2D:4D), and average of both hands (M2D:4D), as well as the right-left-difference (D[R-L]). RESULTS We found no evidence of significant positive intra-couple correlations in our own data, but a significant (positive) meta-analytic effect size estimate emerged for R2D:4D (r = 0.072, p = 0.014). The meta-analytic effects for L2D:4D (r = 0.043, p = 0.303), M2D:4D (r = 0.070, p = 0.225), and D[R-L] (r = 0.028, p = 0.649) were all in the same direction but not statistically significant. However, if the sample from Klimek et al. (2014, 2016) were omitted, meta-analysis would also yield a significant positive correlation for M2D:4D (r = 0.128, p = 0.001). CONCLUSIONS Although our findings are based on a fairly small range of studies, which themselves provide a relatively small sample of participants, they do imply the intriguing possibility of small effects of positive assortment in relation to characteristics associated with the prenatal hormonal environment.
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Affiliation(s)
- Gareth Richards
- School of Psychology, Faculty of Medical Sciences, Newcastle University, UK; Autism Research Centre, Department of Psychiatry, University of Cambridge, UK.
| | - Simon Baron-Cohen
- Autism Research Centre, Department of Psychiatry, University of Cambridge, UK
| | - Tommy van Steen
- Institute of Security and Global Affairs, Universiteit Leiden, Netherlands
| | - John Galvin
- Department of Psychology, Birmingham City University, UK
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Miłkowska K, Nenko I, Klimek M, Galbarczyk A, Jasienska G. Season of birth and biomarkers of early-life environment. Am J Hum Biol 2020; 33:e23532. [PMID: 33166028 DOI: 10.1002/ajhb.23532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 08/21/2020] [Accepted: 10/22/2020] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE Early-life conditions play an important role in human development, affecting health status and survival. Conditions in utero partly depend on the external environment and thus vary in relation to the season of birth. The aim of this study was to investigate if people born in different seasons of the year differ in values of biomarkers that reflect conditions during fetal development. METHODS The study was conducted among Polish rural women recruited at the Mogielica Human Ecology Study Site. The participants were 234 women aged 45 to 92 (mean = 60.2; SD = 10.44). The indicators of early-life environment analyzed in the study were: Absolute Finger Ridge Count (AFRC), the difference between mean number of ridge counts in both thumbs and both little fingers (Md15), overall facial fluctuating asymmetry (OFA), central facial asymmetry (CFA), right and left hand 2D:4D. RESULTS Values of biomarkers of fetal development did not vary among groups of women born in different seasons of the year. CONCLUSIONS Lack of differences in values of biomarkers according to birth season may indicate that: (a) season of birth is not a good indicator of early-life conditions; (b) tested biomarkers do not reliably reflect the prenatal environment; (c) season of birth does not fully overlap with the sensitive periods of biomarker development and thus fails to capture differences in developmental conditions.
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Affiliation(s)
- Karolina Miłkowska
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland
| | - Ilona Nenko
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland
| | - Magdalena Klimek
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland
| | - Andrzej Galbarczyk
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland
| | - Grazyna Jasienska
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland
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Klimek M, Galbarczyk A, Nenko I, Jasienska G. Biomarkers of fetal conditions: Finger ridge-counts, facial fluctuating asymmetry, and digit ratio (2D:4D)-are they correlated in women? AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2020; 174:224-231. [PMID: 33098083 DOI: 10.1002/ajpa.24164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 08/01/2020] [Accepted: 10/10/2020] [Indexed: 11/08/2022]
Abstract
OBJECTIVES Fetal environmental conditions are crucial for life-long health. Direct measurements of developmental conditions are limited in humans; thus, several biomarkers of those conditions have been proposed: that is, finger ridge-counts, level of facial fluctuating asymmetry (FA), and digit ratio (2D:4D). Since all of these biomarkers share a similar gestational time of formation, we hypothesize that their values are significantly correlated. MATERIALS AND METHODS Data were collected at the Mogielica Human Ecology Study Site in southern Poland among 234 women. Finger ridge-counts, level of facial FA, and 2D:4D have been measured. The two-step analyses included Pearson's correlations of simple values of the biomarkers and correlations of composite variables calculated based on principal component analysis. RESULTS We did not find any statistically significant correlations between finger ridge-counts, FA, and 2D:4D in women. Similarly, we did not observe any correlations between three composites created from the biomarkers. DISCUSSION Our results indicate that there are no relationships between the biomarkers, suggested as proxies of the quality of prenatal conditions, in a single population. This is the first study analyzing three different markers simultaneously. The lack of correlations may indicate that the tested biomarkers reflect, in fact, different environmental conditions, occurring in separate "critical windows" of development, or that the biomarkers are not valid as proxies of developmental conditions.
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Affiliation(s)
- Magdalena Klimek
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland
| | - Andrzej Galbarczyk
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland
| | - Ilona Nenko
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland
| | - Grazyna Jasienska
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland
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Kirchengast S, Dottolo E, Praxmarer E, Huber J. Low digit ratio (2D:4D) is associated with early natural menopause. Am J Hum Biol 2019; 32:e23374. [PMID: 31837082 PMCID: PMC7317431 DOI: 10.1002/ajhb.23374] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 12/02/2019] [Accepted: 12/05/2019] [Indexed: 11/09/2022] Open
Abstract
Objectives Intrauterine environmental conditions may affect the number of primordial follicles and in this way the timing of menopause. The aim of the present study was to investigate association patterns between right hand digit ratio, that is, 2D:4D ‐ as an indicator of prenatal androgen and estrogen exposure, and age at menopause. Methods One hundred sixty‐nine women, who had experienced natural menopause, were enrolled in the study. Length of second and fourth finger were measured directly from the palmar side and digit ratios of both hands were calculated. For further analyses the digit ratio of the right hand was used only. Additionally, smoking habits, body weight and body height, body mass index and the number of children were determined. Multiple regression analyses were used to test association patterns between digit ratio and age at menopause, body height, BMI, nicotine consumption as well as number of births and age at menopause. Results Age at menopause correlated significantly positively with the digit ratio. A more feminine digit ratio is associated with a higher age at menopause, while a low digit ratio, interpreted as a hint of a higher androgen exposure during prenatal phase was associated with a lower age at menopause. Conclusions Low digit ratio is associated with an earlier onset of natural menopause.
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Affiliation(s)
- Sylvia Kirchengast
- Department of Evolutionary Anthropology, University of Vienna, Vienna, Austria
| | - Elisabeth Dottolo
- Department of Evolutionary Anthropology, University of Vienna, Vienna, Austria
| | - Elisa Praxmarer
- Department of Evolutionary Anthropology, University of Vienna, Vienna, Austria
| | - Johannes Huber
- Medical University of Vienna, University Clinic for Gynecology and Obstetrics, Vienna, Austria
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Richards G, James TK. A comparison of self-measured and researcher-measured digit ratio (2D:4D). Ann Hum Biol 2019; 46:527-530. [PMID: 31575292 DOI: 10.1080/03014460.2019.1674380] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The largest investigation of digit ratio (2D:4D), the BBC Internet Study, reported on finger lengths measured by participants themselves, yet data validating this technique are scarce and the reliability has been questioned. The current study aimed to calculate reliability and repeatability statistics for self-measured 2D:4D and to examine the correlations with researcher-measures. One hundred and seventy-eight undergraduate psychology students attending a practical class self-measured their finger lengths with rulers; a researcher using digital Vernier calipers measured the second and fourth fingers of a random sub-sample (n = 97). Reliability and repeatability of self-measured 2D:4D were high, as were correlations with researcher-measurements. In each case, lower values were observed for the right-left difference in 2D:4D (D[R-L]). Self-measured L2D:4D and M2D:4D were significantly higher than the equivalent researcher measurements, suggesting that direct comparison could be problematic. Self-measurements and directly made researcher-measurements of 2D:4D are strongly correlated, though self-measured D[R-L] is unreliable.
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Affiliation(s)
- Gareth Richards
- School of Psychology, Newcastle University, Newcastle upon Tyne, UK
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Misiak M, Butovskaya M, Oleszkiewicz A, Sorokowski P. Digit ratio and hand grip strength are associated with male competition outcomes: A study among traditional populations of the Yali and Hadza. Am J Hum Biol 2019; 32:e23321. [PMID: 31512345 DOI: 10.1002/ajhb.23321] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 08/17/2019] [Accepted: 08/28/2019] [Indexed: 01/03/2023] Open
Abstract
OBJECTIVES Indirect measures of physiological features, such as digit ratio and hand grip strength (HGS), are associated with the outcome of male competition activities. However, most of the studies were conducted in developed and industrialized societies. We tested the hypothesis that both digit ratio and HGS are associated with performance in male-specific activities in two traditional preindustrial societies: Yali and Hadza. METHODS To measure masculine behavioral traits, we determined warriorship status (Yali; n = 49) and assessed hunting skills (Yali n = 47 and Hadza n = 49). We also assessed the digit ratio and HGS of each male. We conducted our analyses using the Bayesian approach. RESULTS Bayesian regression models indicated that greater hand grip strength is associated with better hunting outcomes among Hadza males. We did not find a similar link for the Yali. We found anecdotal evidence for the link between left hand digit ratio and the number of birds hunted by Hadza. We found no evidence for the link between digit ratio and performance in male-male competition. CONCLUSIONS Our results suggest that male-male competition outcomes are determined by upper body strength, but only in the Hadza population. We also found limited support for the hypothesis that digit ratio is associated with hunting success among the Hadza. We found no support for the hypothesis concerning the digit ratio or HGS among the Yali. Our research provides partial support for the evolutionary hypotheses based on studies conducted in industrialized populations.
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Affiliation(s)
- Michał Misiak
- Faculty of Historical and Pedagogical Sciences, Institute of Psychology, University of Wroclaw, Wroclaw, Poland
| | - Marina Butovskaya
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Moscow, Russia
| | - Anna Oleszkiewicz
- Faculty of Historical and Pedagogical Sciences, Institute of Psychology, University of Wroclaw, Wroclaw, Poland.,Department of Otorhinolaryngology, Smell and Taste Clinic, Dresden, Germany
| | - Piotr Sorokowski
- Faculty of Historical and Pedagogical Sciences, Institute of Psychology, University of Wroclaw, Wroclaw, Poland
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Paukner A. Digit ratio (2D:4D) and its behavioral correlates in infant rhesus macaques (Macaca mulatta). Dev Psychobiol 2019; 62:992-998. [PMID: 31512755 DOI: 10.1002/dev.21917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 08/16/2019] [Accepted: 08/17/2019] [Indexed: 11/11/2022]
Abstract
2D:4D ratios are typically lower in adult human males than females and are linked to numerous sex-differentiated behaviors. 2D:4D ratios are considered an indicator of prenatal androgen exposure; if so, children's 2D:4D ratios would arguably be even better indicators of prenatal androgen exposure since children have experienced fewer postnatal influences than adults. However, sex differences in 2D:4D ratios as well as associations between 2D:4D ratios and sex-typed behaviors in children have been inconsistent. Several studies also report sex differences and behavioral correlates of 2D:4D ratios in adult non-human primates, but little is known about 2D:4D ratios in infant non-human primates. This study examined sex differences in 2D:4D ratios over the first month of life, and associations with behavioral outcomes at 12-24 weeks of age, in N = 304 infant rhesus macaques. An increase in 2D:4D ratios over the first month of life was found, as well as associations with aggression and play behaviors, but no sex differences in 2D:4D ratios were observed. These results highlight the need for future developmental studies of 2D:4D ratios in order to determine not only their stability and predictive value, but also to discern the mechanism connecting prenatal androgen exposure, 2D:4D ratios, and behavioral outcomes.
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Affiliation(s)
- Annika Paukner
- Psychology Department, Nottingham Trent University, Nottingham, UK
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Zhang K, Yang X, Zhang M, Wang C, Fang P, Xue M, Zhao J, Gao X, Pan R, Gong P. Revisiting the relationships of 2D:4D with androgen receptor (AR) gene and current testosterone levels: Replication study and meta-analyses. J Neurosci Res 2019; 98:353-370. [PMID: 31359506 DOI: 10.1002/jnr.24502] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 07/13/2019] [Accepted: 07/15/2019] [Indexed: 01/07/2023]
Abstract
The relationships of digit ratio (2D:4D) with the length of AR (CAG)n, and testosterone levels from saliva and blood have been extensively debated over the years. This research including three studies further clarifies such controversies. To do so, we re-examined the relationships between the length of AR (CAG)n, 2D:4D, and current testosterone levels, through replication study and meta-analysis for each study. The results indicate: (a) the length of AR (CAG)n is not significantly associated with 2D:4D; (b) current testosterone levels are not significantly associated with the ratio; and (c) the length is not significantly associated with testosterone levels. Thus, AR (CAG)n and current testosterone levels are not significantly related to 2D:4D at individual level.
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Affiliation(s)
- Kejin Zhang
- Shaanxi Key Laboratory for Animal Conservation, Northwest University, Xi'an, China.,College of Life Science, Northwest University, Xi'an, China
| | - Xing Yang
- College of Life Science, Northwest University, Xi'an, China
| | - Mengfei Zhang
- College of Life Science, Northwest University, Xi'an, China
| | - Chunlan Wang
- College of Life Science, Northwest University, Xi'an, China
| | - Pengpeng Fang
- College of Life Science, Northwest University, Xi'an, China
| | - Mengying Xue
- College of Life Science, Northwest University, Xi'an, China
| | - Jing Zhao
- College of Life Science, Northwest University, Xi'an, China
| | - Xiaocai Gao
- Institute of Population and Health, Northwest University, Xi'an, China
| | - Ruliang Pan
- Shaanxi Key Laboratory for Animal Conservation, Northwest University, Xi'an, China.,School of Human Sciences, Centre for Evolutionary Biology, The University of Western Australia, Perth, WA, Australia.,School of Biological Sciences, The University of Western Australia, Perth, WA, Australia
| | - Pingyuan Gong
- Shaanxi Key Laboratory for Animal Conservation, Northwest University, Xi'an, China.,College of Life Science, Northwest University, Xi'an, China.,Institute of Population and Health, Northwest University, Xi'an, China.,Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Northwest University, Xi'an, China
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29
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Crewther BT, Cook CJ. The digit ratio (2D:4D) relationship with testosterone is moderated by physical training: Evidence of prenatal organizational influences on activational patterns of adult testosterone in physically-active women. Early Hum Dev 2019; 131:51-55. [PMID: 30856487 DOI: 10.1016/j.earlhumdev.2019.02.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 02/22/2019] [Accepted: 02/26/2019] [Indexed: 10/27/2022]
Abstract
BACKGROUND The 2nd to 4th digit ratio (2D:4D) is regarded as a sexually dimorphic trait governed by prenatal testosterone (T) and estradiol exposure. However, relationships between the 2D:4D and adult sex hormone concentrations are inconsistent in females. Environmental contingencies (e.g., physical training) may provide a stronger basis for establishing these linkages, particularly if the relationships are plastic and not fixed. AIMS To investigate associations between 2D:4D, training hours and salivary T (sal-T) measures in physically-active women. STUDY DESIGN Descriptive and quasi-experimental monitoring across the follicular (day 7), ovulatory (day 14) and luteal (day 21) phases of three menstrual cycles. SUBJECTS 35 naturally-cycling women training regularly for sport (range 3-12 h a week). OUTCOME MEASURES Morning sal-T concentrations and changes in sal-T to a physical and psychological stimulus (~10 min) were measured. RESULTS Both 2D:4D and training hours were related to morning sal-T concentrations in all three menstrual phases (p < 0.01) and their interaction was significant during ovulation. Follow-up testing revealed a negative 2D:4D and sal-T association in women reporting high, but not low, training hours each week. Participant 2D:4D was also related to sal-T changes under physical and/or psychological challenge across each menstrual phase (p < 0.01), whereas training hours and its interaction with 2D:4D were not significant predictors of these outcomes. CONCLUSIONS 2D:4D linkages with basal and challenge-induced sal-T changes were identified in women undertaking regular physical training. Training hours also moderated the 2D:4D link to morning sal-T, but with some menstrual-phase dependency. These complexities and environmental relationships may help reconcile conflicting results.
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Affiliation(s)
- Blair T Crewther
- Institute of Sport - National Research Institute, Warsaw, Poland; Hamlyn Centre, Imperial College, UK.
| | - Christian J Cook
- Hamlyn Centre, Imperial College, UK; University of Canberra - Research Institute for Sport and Exercise, University of Canberra, Canberra, Australia; School of Sport, Health and Exercise Sciences, Bangor University, Bangor, UK
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30
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Same Same but Different: A Clinical Characterization of Men with Hypersexual Disorder in the Sex@Brain Study. J Clin Med 2019; 8:jcm8020157. [PMID: 30704084 PMCID: PMC6406591 DOI: 10.3390/jcm8020157] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/23/2019] [Accepted: 01/28/2019] [Indexed: 11/17/2022] Open
Abstract
Problems arising from hypersexual behavior are often seen in clinical settings. We aimed to extend the knowledge about the clinical characteristics of individuals with hypersexual disorder (HD). A group of people who fulfilled the proposed diagnostic criteria for HD (men with HD, n = 50) was compared to a group of healthy controls (n = 40). We investigated differences in sociodemographic, neurodevelopmental, and family factors based on self-report questionnaires and clinical interviews. Men with HD reported elevated rates of sexual activity, paraphilias, consumption of child abusive images, and sexual coercive behavior compared to healthy controls. Moreover, rates of affective disorders, attachment difficulties, impulsivity, and dysfunctional emotion regulation strategies were higher in men with HD. Men with HD seem to have experienced various forms of adverse childhood experiences, but there were no further differences in sociodemographic, neurodevelopmental factors, and family factors. Regression analyses indicated that attachment-related avoidance and early onset of masturbation differentiated between men with HD and healthy controls. In conclusion, men with HD appear to have the same neurodevelopment, intelligence levels, sociodemographic background, and family factors compared to healthy controls, but they report different and adverse experiences in childhood, problematic sexual behavior, and psychological difficulties.
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31
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Nishimura Y, Moriya K, Kobayashi S, Araki A, Sata F, Mitsui T, Itoh S, Miyashita C, Cho K, Kon M, Nakamura M, Kitta T, Murai S, Kishi R, Shinohara N. Association between ESR1 polymorphisms and second to fourth digit ratio in school-aged children in the Hokkaido Study. Steroids 2019; 141:55-62. [PMID: 30468784 DOI: 10.1016/j.steroids.2018.11.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 11/14/2018] [Accepted: 11/17/2018] [Indexed: 01/28/2023]
Abstract
The ratio of the lengths of the 2nd and 4th digits (2D:4D) is considered an index of prenatal exposure to androgen. Indeed, androgen receptors have been linked to digit length, but estrogen receptors are rarely investigated in this context. Thus, we investigated the association between estrogen receptor 1 (ESR1) genetic polymorphisms and 2D:4D in school-aged children. The 2D:4D ratios were determined using Vernier calipers from photocopies of palms provided by 1800 children aged 7 years who were enrolled in an ongoing prospective cohort study in Hokkaido, Japan. The children were genotyped using cord blood collected at birth for single nucleotide polymorphisms in ESR1, specifically PvuII (T > C, dbSNP: rs2234693), XbaI (A > G, dbSNP: rs9340799), and rs2077647 (A > G). The association between ESR1 polymorphisms and 2D:4D was assessed by multiple linear regression adjusted for potential cofounding factors. Boys with the GG genotype at rs9340799 had a significantly lower 2D:4D in the right hand than boys with the AA/AG genotype (-0.96% lower, 95% confidence interval: -1.68 to -0.24). However, this association was detected only in boys born to non-smoking mothers. No significant differences were found between rs9340799 polymorphisms and 2D:4D among girls. There was also no link between 2D:4D and polymorphisms at rs2234693 and rs2077647. These data suggest that rs9340799 polymorphisms in ESR1 may contribute to digit length and 2D:4D.
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Affiliation(s)
- Yoko Nishimura
- Department of Renal and Genitourinary Surgery, Hokkaido University Graduate School of Medicine, North-15, West-7, Kita-ku, Sapporo 060-8638, Japan; Center for Environmental and Health Sciences, Hokkaido University, North-12, West-7, Kita-ku, Sapporo 060-0812, Japan
| | - Kimihiko Moriya
- Department of Renal and Genitourinary Surgery, Hokkaido University Graduate School of Medicine, North-15, West-7, Kita-ku, Sapporo 060-8638, Japan.
| | - Sumitaka Kobayashi
- Center for Environmental and Health Sciences, Hokkaido University, North-12, West-7, Kita-ku, Sapporo 060-0812, Japan
| | - Atsuko Araki
- Center for Environmental and Health Sciences, Hokkaido University, North-12, West-7, Kita-ku, Sapporo 060-0812, Japan
| | - Fumihiro Sata
- Center for Environmental and Health Sciences, Hokkaido University, North-12, West-7, Kita-ku, Sapporo 060-0812, Japan; Health Center, Chuo University, 42-8, Ichigaya-Hommura-cho, Shinjuku-ku, Tokyo 162-8473, Japan
| | - Takahiko Mitsui
- Department of Urology, Graduate School of Medical Science, University of Yamanashi, Simokato-1110, Chuo 409-3898, Japan
| | - Sachiko Itoh
- Center for Environmental and Health Sciences, Hokkaido University, North-12, West-7, Kita-ku, Sapporo 060-0812, Japan
| | - Chihiro Miyashita
- Center for Environmental and Health Sciences, Hokkaido University, North-12, West-7, Kita-ku, Sapporo 060-0812, Japan
| | - Kazutoshi Cho
- Maternity and Perinatal Care Center, Hokkaido University Hospital, North-14, West-5 Kita-ku, Sapporo 060-8648, Japan
| | - Masafumi Kon
- Department of Renal and Genitourinary Surgery, Hokkaido University Graduate School of Medicine, North-15, West-7, Kita-ku, Sapporo 060-8638, Japan
| | - Michiko Nakamura
- Department of Renal and Genitourinary Surgery, Hokkaido University Graduate School of Medicine, North-15, West-7, Kita-ku, Sapporo 060-8638, Japan
| | - Takeya Kitta
- Department of Renal and Genitourinary Surgery, Hokkaido University Graduate School of Medicine, North-15, West-7, Kita-ku, Sapporo 060-8638, Japan
| | - Sachiyo Murai
- Department of Renal and Genitourinary Surgery, Hokkaido University Graduate School of Medicine, North-15, West-7, Kita-ku, Sapporo 060-8638, Japan
| | - Reiko Kishi
- Center for Environmental and Health Sciences, Hokkaido University, North-12, West-7, Kita-ku, Sapporo 060-0812, Japan
| | - Nobuo Shinohara
- Department of Renal and Genitourinary Surgery, Hokkaido University Graduate School of Medicine, North-15, West-7, Kita-ku, Sapporo 060-8638, Japan
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32
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Borráz-León JI, Rantala MJ, Cerda-Molina AL. Digit ratio (2D:4D) and facial fluctuating asymmetry as predictors of the dark triad of personality. PERSONALITY AND INDIVIDUAL DIFFERENCES 2019. [DOI: 10.1016/j.paid.2018.08.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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33
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Bakholdina VY, Movsesian AA, Negasheva MA. Association between the digit ratio (2D:4D) and body fat distribution in Mordovian students. Ann Hum Biol 2018; 45:414-418. [PMID: 30328710 DOI: 10.1080/03014460.2018.1495264] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
BACKGROUND The length ratio of the second to the fourth finger (2D:4D) is a possible biomarker of prenatal sex hormone levels, which play a significant role in determining sex-related body traits. AIMS To evaluate the value of the 2D:4D ratio in a Mordovian sample and to test the associations between the 2D:4D ratio and sexually dimorphic morphological traits, such as height and body weight, body mass index, waist and hip circumference, the waist-to-hip ratio, handgrip strength and the skinfold thickness. SUBJECTS AND METHODS The sample studied included 106 individuals of Mordovian ethnicity: 58 males and 48 females, 16-23 years old. The associations between the 2D:4D ratio and morphological traits were evaluated by multivariate regression analysis and correlation analysis. RESULTS The 2D:4D ratio in males was significantly lower than in females. Most of the associations of the 2D:4D ratio with morphological traits were statistically insignificant. The 2D:4D ratio is only significantly correlated with skinfold thickness of the forearm and the abdomen in females. CONCLUSION The association between the 2D:4D ratio and skinfold thickness is indicative of the role of prenatal sex hormones in shaping the body fat distribution in females, along with the significant impact of sex hormones at puberty.
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Affiliation(s)
| | - Alla A Movsesian
- a Department of Anthropology , Lomonosov State University , Moscow , Russian
| | - Marina A Negasheva
- a Department of Anthropology , Lomonosov State University , Moscow , Russian
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34
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Shere M, Arbuckle TE, Monnier P, Fraser W, Velez MP. Time-to-pregnancy and offspring finger-length ratio (2D:4D). Am J Hum Biol 2018; 30:e23176. [PMID: 30329191 DOI: 10.1002/ajhb.23176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 06/28/2018] [Accepted: 08/01/2018] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVES Time-to-Pregnancy (TTP) is an epidemiological tool to assess couple fecundity. The finger digit ratio (2D:4D) has been suggested as a marker of androgen exposure in utero. Maternal, paternal, or couple-mediated factors related to fecundity may also have an effect on androgen exposure during pregnancy. We aimed to investigate the association between TTP, infertility, or use of Assisted Reproductive Technologies (ART) and offspring 2D:4D. METHODS Data from 673 mother-child pairs were collected from questionnaires in the Maternal-Infant Research on Environmental Chemicals (MIREC) study across 10 cities in Canada. The mean maternal age was 33.4 years (SD 4.7), with a median gestational age of 12.1 weeks (SD 1.3), at the time of recruitment. Our study included 338 girls and 335 boys, and the mean age of the children at follow-up was 3.5 years (SD 1.0). TTP was assessed through questionnaires during the first trimester of pregnancy. Digital photographs of both hands were taken in a follow-up study to calculate the children's 2D:4D (2-5 years). anova, t tests, and multiple linear regression analyses were conducted. RESULTS Boys had significantly lower mean 2D:4Ds (0.936 ±0.041 in right hand, 0.936 ±0.040 in left hand) compared to girls (0.948 ±0.038 in right hand, 0.945 ±0.038 in left hand). The mean 2D:4D did not differ according to TTP, infertility, or use of ART. The only factors associated with the child's 2D:4D were the child's age and maternal 2D:4D. CONCLUSIONS Our study does not support an association between TTP, infertility, or use of ART and children's 2D:4D.
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Affiliation(s)
- Mahvash Shere
- School of Medicine, Queen's University, Kingston, Canada
| | - Tye E Arbuckle
- Targeted Epidemiology and Biomonitoring Section, Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Ottawa, Canada
| | - Patricia Monnier
- Department of Obstetrics and Gynecology, McGill University Health Centre, Montreal, Canada
| | - William Fraser
- Sainte-Justine University Hospital Research Centre, University of Montreal, Montreal, Canada.,Department of Obstetrics and Gynecology, University of Sherbrooke, Quebec, Canada
| | - Maria P Velez
- Department of Obstetrics and Gynaecology, Division of Reproductive Endocrinology and Infertility, Queen's University, Kingston, Canada
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35
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Warrington NM, Shevroja E, Hemani G, Hysi PG, Jiang Y, Auton A, Boer CG, Mangino M, Wang CA, Kemp JP, McMahon G, Medina-Gomez C, Hickey M, Trajanoska K, Wolke D, Ikram MA, Montgomery GW, Felix JF, Wright MJ, Mackey DA, Jaddoe VW, Martin NG, Tung JY, Davey Smith G, Pennell CE, Spector TD, van Meurs J, Rivadeneira F, Medland SE, Evans DM. Genome-wide association study identifies nine novel loci for 2D:4D finger ratio, a putative retrospective biomarker of testosterone exposure in utero. Hum Mol Genet 2018; 27:2025-2038. [PMID: 29659830 PMCID: PMC5961159 DOI: 10.1093/hmg/ddy121] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Revised: 03/12/2018] [Accepted: 04/03/2018] [Indexed: 02/06/2023] Open
Abstract
The ratio of the length of the index finger to that of the ring finger (2D:4D) is sexually dimorphic and is commonly used as a non-invasive biomarker of prenatal androgen exposure. Most association studies of 2D:4D ratio with a diverse range of sex-specific traits have typically involved small sample sizes and have been difficult to replicate, raising questions around the utility and precise meaning of the measure. In the largest genome-wide association meta-analysis of 2D:4D ratio to date (N = 15 661, with replication N = 75 821), we identified 11 loci (9 novel) explaining 3.8% of the variance in mean 2D:4D ratio. We also found weak evidence for association (β = 0.06; P = 0.02) between 2D:4D ratio and sensitivity to testosterone [length of the CAG microsatellite repeat in the androgen receptor (AR) gene] in females only. Furthermore, genetic variants associated with (adult) testosterone levels and/or sex hormone-binding globulin were not associated with 2D:4D ratio in our sample. Although we were unable to find strong evidence from our genetic study to support the hypothesis that 2D:4D ratio is a direct biomarker of prenatal exposure to androgens in healthy individuals, our findings do not explicitly exclude this possibility, and pathways involving testosterone may become apparent as the size of the discovery sample increases further. Our findings provide new insight into the underlying biology shaping 2D:4D variation in the general population.
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Affiliation(s)
- Nicole M Warrington
- The University of Queensland Diamantina Institute, Translational Research Institute, University of Queensland, Brisbane, QLD 4102, Australia
- Queensland Institute of Medical Research, Brisbane, QLD 4006, Australia
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, WA 6009, Australia
| | - Enisa Shevroja
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, South Holland, The Netherlands
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
| | - Gibran Hemani
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol BS8 2BN, UK
- Population Health Sciences, University of Bristol, Bristol BS8 2PS, UK
| | - Pirro G Hysi
- Department of Twin Research and Genetic Epidemiology, King’s College London, London SE1 7EH, UK
| | | | - Adam Auton
- 23andMe, Inc., Mountain View, CA 94061, USA
| | - Cindy G Boer
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
| | - Massimo Mangino
- Department of Twin Research and Genetic Epidemiology, King’s College London, London SE1 7EH, UK
| | - Carol A Wang
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, WA 6009, Australia
- School of Medicine and Public Health, Faculty of Medicine and Health, The University of Newcastle, Newcastle, NSW 2308, Australia
| | - John P Kemp
- The University of Queensland Diamantina Institute, Translational Research Institute, University of Queensland, Brisbane, QLD 4102, Australia
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol BS8 2BN, UK
- Population Health Sciences, University of Bristol, Bristol BS8 2PS, UK
| | - George McMahon
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol BS8 2BN, UK
- Population Health Sciences, University of Bristol, Bristol BS8 2PS, UK
| | - Carolina Medina-Gomez
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, South Holland, The Netherlands
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, Netherlands
| | - Martha Hickey
- Department of Obstetrics and Gynaecology, The University of Melbourne and the Royal Women’s Hospital, Parkville, VIC 3052, Australia
| | - Katerina Trajanoska
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, Netherlands
| | - Dieter Wolke
- Department of Psychology and Warwick Medical School, University of Warwick, Coventry CV47AL, UK
| | - M Arfan Ikram
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, Netherlands
| | | | - Grant W Montgomery
- Queensland Brain Institute and Centre for Advanced Imaging, University of Queensland, Brisbane, QLD 4072, Australia
| | - Janine F Felix
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, South Holland, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, Netherlands
- Department of Pediatrics, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
| | - Margaret J Wright
- Queensland Brain Institute and Centre for Advanced Imaging, University of Queensland, Brisbane, QLD 4072, Australia
| | - David A Mackey
- Lions Eye Institute, Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, WA 6009, Australia
| | - Vincent W Jaddoe
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, South Holland, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, Netherlands
- Department of Pediatrics, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
| | - Nicholas G Martin
- Queensland Institute of Medical Research, Brisbane, QLD 4006, Australia
| | | | - George Davey Smith
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol BS8 2BN, UK
- Population Health Sciences, University of Bristol, Bristol BS8 2PS, UK
| | - Craig E Pennell
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, WA 6009, Australia
- School of Medicine and Public Health, Faculty of Medicine and Health, The University of Newcastle, Newcastle, NSW 2308, Australia
| | - Tim D Spector
- Department of Twin Research and Genetic Epidemiology, King’s College London, London SE1 7EH, UK
| | - Joyce van Meurs
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, South Holland, The Netherlands
| | - Fernando Rivadeneira
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, South Holland, The Netherlands
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, Netherlands
| | - Sarah E Medland
- Queensland Institute of Medical Research, Brisbane, QLD 4006, Australia
| | - David M Evans
- The University of Queensland Diamantina Institute, Translational Research Institute, University of Queensland, Brisbane, QLD 4102, Australia
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol BS8 2BN, UK
- Population Health Sciences, University of Bristol, Bristol BS8 2PS, UK
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Warrington NM, Shevroja E, Hemani G, Hysi PG, Jiang Y, Auton A, Boer CG, Mangino M, Wang CA, Kemp JP, McMahon G, Medina-Gomez C, Hickey M, Trajanoska K, Wolke D, Ikram MA, Montgomery GW, Felix JF, Wright MJ, Mackey DA, Jaddoe VW, Martin NG, Tung JY, Davey Smith G, Pennell CE, Spector TD, van Meurs J, Rivadeneira F, Medland SE, Evans DM. Genome-wide association study identifies nine novel loci for 2D:4D finger ratio, a putative retrospective biomarker of testosterone exposure in utero. Hum Mol Genet 2018; 27:2025-2038. [PMID: 29659830 PMCID: PMC5961159 DOI: 10.1093/hmg/ddy121 10.1093/hmg/ddy121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Revised: 03/12/2018] [Accepted: 04/03/2018] [Indexed: 10/22/2023] Open
Abstract
The ratio of the length of the index finger to that of the ring finger (2D:4D) is sexually dimorphic and is commonly used as a non-invasive biomarker of prenatal androgen exposure. Most association studies of 2D:4D ratio with a diverse range of sex-specific traits have typically involved small sample sizes and have been difficult to replicate, raising questions around the utility and precise meaning of the measure. In the largest genome-wide association meta-analysis of 2D:4D ratio to date (N = 15 661, with replication N = 75 821), we identified 11 loci (9 novel) explaining 3.8% of the variance in mean 2D:4D ratio. We also found weak evidence for association (β = 0.06; P = 0.02) between 2D:4D ratio and sensitivity to testosterone [length of the CAG microsatellite repeat in the androgen receptor (AR) gene] in females only. Furthermore, genetic variants associated with (adult) testosterone levels and/or sex hormone-binding globulin were not associated with 2D:4D ratio in our sample. Although we were unable to find strong evidence from our genetic study to support the hypothesis that 2D:4D ratio is a direct biomarker of prenatal exposure to androgens in healthy individuals, our findings do not explicitly exclude this possibility, and pathways involving testosterone may become apparent as the size of the discovery sample increases further. Our findings provide new insight into the underlying biology shaping 2D:4D variation in the general population.
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Affiliation(s)
- Nicole M Warrington
- The University of Queensland Diamantina Institute, Translational Research Institute, University of Queensland, Brisbane, QLD 4102, Australia
- Queensland Institute of Medical Research, Brisbane, QLD 4006, Australia
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, WA 6009, Australia
| | - Enisa Shevroja
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, South Holland, The Netherlands
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
| | - Gibran Hemani
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol BS8 2BN, UK
- Population Health Sciences, University of Bristol, Bristol BS8 2PS, UK
| | - Pirro G Hysi
- Department of Twin Research and Genetic Epidemiology, King’s College London, London SE1 7EH, UK
| | | | - Adam Auton
- 23andMe, Inc., Mountain View, CA 94061, USA
| | - Cindy G Boer
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
| | - Massimo Mangino
- Department of Twin Research and Genetic Epidemiology, King’s College London, London SE1 7EH, UK
| | - Carol A Wang
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, WA 6009, Australia
- School of Medicine and Public Health, Faculty of Medicine and Health, The University of Newcastle, Newcastle, NSW 2308, Australia
| | - John P Kemp
- The University of Queensland Diamantina Institute, Translational Research Institute, University of Queensland, Brisbane, QLD 4102, Australia
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol BS8 2BN, UK
- Population Health Sciences, University of Bristol, Bristol BS8 2PS, UK
| | - George McMahon
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol BS8 2BN, UK
- Population Health Sciences, University of Bristol, Bristol BS8 2PS, UK
| | - Carolina Medina-Gomez
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, South Holland, The Netherlands
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, Netherlands
| | - Martha Hickey
- Department of Obstetrics and Gynaecology, The University of Melbourne and the Royal Women’s Hospital, Parkville, VIC 3052, Australia
| | - Katerina Trajanoska
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, Netherlands
| | - Dieter Wolke
- Department of Psychology and Warwick Medical School, University of Warwick, Coventry CV47AL, UK
| | - M Arfan Ikram
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, Netherlands
| | | | - Grant W Montgomery
- Queensland Brain Institute and Centre for Advanced Imaging, University of Queensland, Brisbane, QLD 4072, Australia
| | - Janine F Felix
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, South Holland, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, Netherlands
- Department of Pediatrics, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
| | - Margaret J Wright
- Queensland Brain Institute and Centre for Advanced Imaging, University of Queensland, Brisbane, QLD 4072, Australia
| | - David A Mackey
- Lions Eye Institute, Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, WA 6009, Australia
| | - Vincent W Jaddoe
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, South Holland, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, Netherlands
- Department of Pediatrics, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
| | - Nicholas G Martin
- Queensland Institute of Medical Research, Brisbane, QLD 4006, Australia
| | | | - George Davey Smith
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol BS8 2BN, UK
- Population Health Sciences, University of Bristol, Bristol BS8 2PS, UK
| | - Craig E Pennell
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, WA 6009, Australia
- School of Medicine and Public Health, Faculty of Medicine and Health, The University of Newcastle, Newcastle, NSW 2308, Australia
| | - Tim D Spector
- Department of Twin Research and Genetic Epidemiology, King’s College London, London SE1 7EH, UK
| | - Joyce van Meurs
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, South Holland, The Netherlands
| | - Fernando Rivadeneira
- The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, South Holland, The Netherlands
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, 3015 CN, Rotterdam, Netherlands
| | - Sarah E Medland
- Queensland Institute of Medical Research, Brisbane, QLD 4006, Australia
| | - David M Evans
- The University of Queensland Diamantina Institute, Translational Research Institute, University of Queensland, Brisbane, QLD 4102, Australia
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol BS8 2BN, UK
- Population Health Sciences, University of Bristol, Bristol BS8 2PS, UK
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Zurawiecka M, Wronka I. Association of primary dysmenorrhea with anthropometrical and socio-economic factors in Polish university students. J Obstet Gynaecol Res 2018; 44:1259-1267. [PMID: 29673014 DOI: 10.1111/jog.13645] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 02/21/2018] [Indexed: 01/19/2023]
Abstract
AIMS To examine the prevalence and factors correlated with primary dysmenorrhea in young female subjects. METHODS Cross-sectional research was conducted among 1305 female university students aged 19-25 years. The following measurements were taken: height, body mass, waist circumference, hip circumference, the length of index and ring finger. A questionnaire was used to obtain information on menstrual pains, the characteristics of the menstrual cycles (regularity, duration), the number of the days of menstrual bleeding, age at menarche, overall health and socio-economic status of the subjects. RESULTS The prevalence of primary dysmenorrhea (PD) in the group was 64.85%, of which 69.60% reported mild pain, and 30.40% moderate and severe pain. PD occurs more frequently both in women with excess and insufficient level of abdominal adiposity. PD occurred more frequently in women who experience first menstruation at earlier age than in women with average and late age at menarche. The prevalence of PD grew along with mother's education and fell along with father's education. Painful menstruations occurred most commonly in women from large families. The impact of the age at menarche and the presence of abnormal body mass and abnormal level of abdominal adiposity on the prevalence of painful menstruation was also confirmed by the results of logistic regression analysis. The risk of PD is the highest in women whose finger 4 is longer than finger 2. CONCLUSION The results suggest that healthy body mass and lack of abdominal obesity may reduce the risk of PD.
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Affiliation(s)
- Martyna Zurawiecka
- Department of Anthropology, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Krakow, Poland
| | - Iwona Wronka
- Department of Anthropology, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Krakow, Poland
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Kuna B, Galbarczyk A. Men with more masculine digit ratios are partnered with more attractive women. PERSONALITY AND INDIVIDUAL DIFFERENCES 2018. [DOI: 10.1016/j.paid.2017.11.040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Richards G, Klimek M, Jasienska G, Marcinkowska UM. Digit ratio (2D:4D) and circulating testosterone, oestradiol, and progesterone levels across the menstrual cycle. Early Hum Dev 2018; 117:68-73. [PMID: 29324286 DOI: 10.1016/j.earlhumdev.2017.12.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 12/04/2017] [Accepted: 12/05/2017] [Indexed: 12/15/2022]
Abstract
BACKGROUND Digit ratio (2D:4D) is used by researchers as an indicator of prenatal sex hormone exposure. Two previous studies have examined associations between 2D:4D and circulating sex steroid concentrations across the menstrual cycle in adult females. One reported that digit ratio correlated positively with oestradiol levels, whereas the other found no such effect; neither observed significant associations with progesterone. AIMS To examine associations between 2D:4D, as well as asymmetry (i.e. right minus left 2D:4D), and circulating sex steroids across the menstrual cycle. STUDY DESIGN Correlational. SUBJECTS 32 naturally cycling adult females from rural southern Poland. OUTCOME MEASURES Salivary oestradiol, progesterone, testosterone, and testosterone to oestradiol ratio (T:O) measured during the follicular, peri-ovulatory, and luteal phases. Average levels across the cycle were also examined. RESULTS AND CONCLUSIONS Asymmetry in digit ratio correlated positively with oestradiol at each phase, as well as with average levels across the cycle. Each association, other than that relating to average levels, remained statistically significant after a range of covariates had been controlled for. No other significant correlations were observed between digit ratio variables and circulating hormone levels. Our results might suggest that low exposure to androgens and/or high exposure to oestrogens during gestation is a predictor of high oestradiol levels in naturally cycling females of reproductive age. However, considering that it was asymmetry in digit ratio, and not either right or left 2D:4D, that was a significant predictor, it is also possible that these effects reflect more general associations between bilateral asymmetry and circulating oestradiol levels.
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Affiliation(s)
- Gareth Richards
- Autism Research Centre, Department of Psychiatry, University of Cambridge, UK.
| | - Magdalena Klimek
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Poland
| | - Grazyna Jasienska
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Poland
| | - Urszula M Marcinkowska
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Poland
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Vásquez-Amézquita M, Leongómez JD, Seto MC, Bonilla FM, Rodríguez-Padilla A, Salvador A. No relation between digit ratio (2D:4D) and visual attention patterns to sexually preferred and non-preferred stimuli. PERSONALITY AND INDIVIDUAL DIFFERENCES 2018. [DOI: 10.1016/j.paid.2017.08.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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41
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Gao Z, Yang Q, Ma X, Becker B, Li K, Zhou F, Kendrick KM. Men Who Compliment a Woman's Appearance Using Metaphorical Language: Associations with Creativity, Masculinity, Intelligence and Attractiveness. Front Psychol 2017; 8:2185. [PMID: 29312054 PMCID: PMC5742614 DOI: 10.3389/fpsyg.2017.02185] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 11/30/2017] [Indexed: 12/12/2022] Open
Abstract
Language may have evolved as a signal of mental fitness. However, it remains unclear what language form and topic men use to covertly signal mate quality. In this study 69 men created compliments to impress unfamiliar women they chose to either date or work with and provided hand scans to compute 2D4D ratio as a proxy for prenatal testosterone exposure and masculinity indicator. Compliments were coded in terms of form (literal vs. metaphorical) and topic (women's appearance vs. non-appearance), with metaphorical ones being subsequently rated by 114 women for psycholinguistic features, indices of intelligence and willingness to have a romantic relationship with the author. Results showed that in a dating context, men produced more metaphorical form compliments targeting appearance compared to the working context and they were associated with men's art creativity and negatively with 2D4D ratio (i.e., positively with masculinity). Women preferred establishing a romantic relationship with a higher proportion of the men producing metaphorical compliments in a dating than a working context. Furthermore, in the dating but not the working context, women perceived men producing such compliments as being more intelligent, and importantly this correlated with the men's actual verbal intelligence. Overall, findings suggest that men may use metaphorical language compliments targeting women's appearance in a dating context to signal covertly their mate quality.
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Affiliation(s)
- Zhao Gao
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China.,School of Foreign Languages, University of Electronic Science and Technology of China, Chengdu, China.,Key Laboratory for Neuroinformation, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Qi Yang
- School of Foreign Languages, University of Electronic Science and Technology of China, Chengdu, China
| | - Xiaole Ma
- Key Laboratory for Neuroinformation, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Benjamin Becker
- Key Laboratory for Neuroinformation, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Keshuang Li
- Key Laboratory for Neuroinformation, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Feng Zhou
- Key Laboratory for Neuroinformation, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Keith M Kendrick
- Key Laboratory for Neuroinformation, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, China
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Georgiev AV, Ryan CP, Borja JB, Kuzawa CW. Is early postnatal growth velocity, a proxy of minipubertal androgen action, related to adult second‐to‐fourth digit (2D:4D) ratios in men? A test in Cebu, Philippines. Am J Hum Biol 2017; 29. [DOI: 10.1002/ajhb.23047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 05/25/2017] [Accepted: 07/05/2017] [Indexed: 12/19/2022] Open
Affiliation(s)
- Alexander V. Georgiev
- Department of AnthropologyNorthwestern University1810 Hinman Avenue, Evanston Illinois60208
- School of Biological SciencesBangor University, Deiniol RoadBangor GwyneddLL57 2UW United Kingdom
| | - Calen P. Ryan
- Department of AnthropologyNorthwestern University1810 Hinman Avenue, Evanston Illinois60208
| | - Judith B. Borja
- Office of Population Studies Foundation, Inc. and Department of Nutrition and Dietetics, University of San CarlosCebu City Philippines
| | - Christopher W. Kuzawa
- Department of AnthropologyNorthwestern University1810 Hinman Avenue, Evanston Illinois60208
- Institute for Policy ResearchNorthwestern University2040 Sheridan Road, Evanston Illinois60208
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Klimek M, Marcinkowska UM, Jasienska G. Value of digit ratio 2D:4D, a biomarker of prenatal hormone exposure, is stable across the menstrual cycle. Early Hum Dev 2017; 110:21-24. [PMID: 28499133 DOI: 10.1016/j.earlhumdev.2017.04.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 04/21/2017] [Accepted: 04/25/2017] [Indexed: 12/14/2022]
Abstract
Digit ratio (2D:4D) is used as a marker of prenatal hormone exposure and, consequently, as a predictor of many characteristics throughout a woman's lifespan. A previous study has suggested that values of 2D:4D vary across menstrual cycles and further questioned the reliability of a single measurement of 2D:4D among cycling women, while another study failed to confirm these results. However, these studies estimated the timing of cycle phases based on a date of menstruation reported by participants and also had small sample sizes. For our study, we evaluated potential changes in 2D:4D values across a menstrual cycle in a group of women among whom the phases of the menstrual cycle were determined by hormonal (luteinizing hormone based) ovulation tests. We studied 32 naturally cycling women aged 22-37 from rural Poland. Lengths of second and fourth digits were measured based on scans of both hands taken three times (i.e. in the follicular phase, peri-ovulatory phase and luteal phase of the cycle) for each participant. No differences in 2D:4D value across the menstrual cycle were detected either when right-hand, left-hand, and mean 2D:4D for both hands were analysed, nor when difference in the 2D:4D value between hands (Dleft-right) was evaluated. We documented that 2D:4D is independent of the phase of the menstrual cycle and these findings suggest that among naturally cycling women, a value of 2D:4D can be reliably obtained from measurements taken during any day of the menstrual cycle.
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Affiliation(s)
- Magdalena Klimek
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Grzegorzecka 20, 31-531 Krakow, Poland.
| | - Urszula M Marcinkowska
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Grzegorzecka 20, 31-531 Krakow, Poland.
| | - Grazyna Jasienska
- Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, Grzegorzecka 20, 31-531 Krakow, Poland.
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Is maternal periconceptional smoking associated with 2D:4D digit ratio in their children? J Dev Orig Health Dis 2017; 8:597-603. [DOI: 10.1017/s2040174417000320] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The 2nd--4th finger ratio (2D:4D) has been proposed as a potential indicator of greater androgen exposure during fetal development. Maternal periconceptional smoking may alter the homeostasis of fetal androgens, which could in turn result in differential development of 2D:4Ds in utero. The aim of the present study was to assess the effect of maternal periconceptional smoking (i.e. 1 year before through the first trimester of pregnancy) on the 2D:4D of children within The Maternal-Infant Research on Environmental Chemicals (MIREC) study. Maternal smoking history was obtained through questionnaires during the first trimester of pregnancy in 2001 women from 10 cities across Canada. The periconceptional smoking prevalence was 12%. A follow-up study was conducted to measure growth and development up to 5 years of age in a subsample of some 800 MIREC children (MIREC-CD Plus), and digital pictures of the ventral surface of both hands were obtained in mothers and children (2–5 years). The 2D:4D was calculated as the ratio of the 2nd and 4th fingers of each hand. Boys had lower mean 2D:4Ds compared with girls in both hands. Age and maternal 2D:4D were strong determinants of the children’s 2D:4D, however, the mean 2D:4D did not differ among children whose mothers had smoked during the periconceptional period compared with those who had not, irrespective of sex. In conclusion, we did not find an association between maternal periconceptional smoking and children’s 2D:4D, although the smoking prevalence was low.
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Georgiev AV, Ryan CP, Gettler LT, McDade TW, Kuzawa CW. Second‐to‐fourth digit ratio (2D:4D) is unrelated to measures of somatic reproductive effort among young men from Cebu, the Philippines. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2017; 163:437-445. [DOI: 10.1002/ajpa.23215] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 02/24/2017] [Accepted: 03/10/2017] [Indexed: 12/18/2022]
Affiliation(s)
| | - Calen P. Ryan
- Department of AnthropologyNorthwestern UniversityEvanston Illinois
| | - Lee T. Gettler
- Department of AnthropologyUniversity of Notre DameNotre Dame Indiana
- The Eck Institute for Global HealthUniversity of Notre DameNotre Dame Indiana
| | - Thomas W. McDade
- Department of AnthropologyNorthwestern UniversityEvanston Illinois
- Institute for Policy ResearchNorthwestern UniversityEvanston Illinois
| | - Christopher W. Kuzawa
- Department of AnthropologyNorthwestern UniversityEvanston Illinois
- Institute for Policy ResearchNorthwestern UniversityEvanston Illinois
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Vélez MP, Arbuckle TE, Monnier P, Fraser WD. Female digit length ratio (2D:4D) and time-to-pregnancy. Hum Reprod 2016; 31:2128-34. [PMID: 27343270 DOI: 10.1093/humrep/dew164] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 06/03/2016] [Indexed: 11/14/2022] Open
Abstract
STUDY QUESTION Is the female 2th- to 4th-finger ratio (2D:4D) associated with fecundity as measured by time-to-pregnancy (TTP)? SUMMARY ANSWER Our study does not support an association between female 2D:4D and TTP. WHAT IS KNOWN ALREADY The 2th- to 4th-finger ratio (2D:4D) has been proposed as a potential indicator of greater androgen exposure during fetal development. Women exposed in utero to unbalanced steroid hormones may have impaired fecundity in the adulthood. Fecundity is often measured by TTP, an epidemiological tool commonly used to assess the impact of environmental factors in human conception. STUDY DESIGN, SIZE, DURATION The Maternal-Infant Research on Environmental Chemicals (MIREC) Study is a pregnancy and birth cohort of 2001 women recruited before 14 weeks of gestation in 10 cities across Canada between 2008 and 2011. The present analysis is part of MIREC-CD Plus, a follow-up study in a subsample of some 800 MIREC mothers and their children from 2012 to 2015. PARTICIPANTS/MATERIALS, SETTING, METHODS TTP and maternal characteristics were collected from questionnaires administered during the first trimester of pregnancy as part of the MIREC study. Digital pictures of the ventral surface of both hands were obtained in the MIREC mothers at the MIREC-CD Plus follow-up study. The 2D:4D was calculated as the ratio of the second and fourth fingers of each hand. The exposure of interest was the 2D:4D of the women categorized by tertiles, or dichotomized as ≥1 (index finger longer than the ring finger) or <1 (ring finger longer than the index finger, implying greater androgen exposure during fetal development). The final sample included 696 mothers. Statistical analyses included discrete-time Cox proportional hazard models, allowing adjustment for potential confounding factors. MAIN RESULTS AND THE ROLE OF CHANCE There was no evidence of diminished/increased fecundability according to the 2D:4D, neither on the right nor on the left hand. In our analysis by tertiles, the smallest 2D:4D (i.e. higher androgen exposure during fetal life) resulted in FORs higher than 1 (i.e. shorter TTP) in both hands, although this was not statistically significant (FOR 1.19 [95% CI 0.93, 1.51] in the right hand and 1.16 [95% CI 0.91, 1.47] in the left hand). In the dichotomous analysis, 2D:4D <1 resulted in FORs higher than 1 (i.e. shorter TTP), but this was also not statistically significant (FOR 1.08 [95% CI 0.88, 1.33] in the right hand and 1.14 [95% CI 0.92, 1.42] in the left hand). Our large sample size resulted in a high statistical power to exclude an association between female 2D:4D and TTP. LIMITATIONS, REASONS FOR CAUTION The MIREC Study is a cohort of pregnant women, and therefore, women with infertility were excluded by design from our study. WIDER IMPLICATIONS OF THE FINDINGS Our data do not provide evidence for an association between female 2D:4D and fecundity as measured by TTP. Whether the female 2D:4D is a marker of in utero androgen exposure and whether it is associated with fecundity have yet to be determined. STUDY FUNDING/COMPETING INTEREST The MIREC Study was funded by Health Canada's Chemicals Management Plan, the Canadian Institute of Health Research (CIHR grant # MOP - 81285), and the Ontario Ministry of the Environment. MIREC-CD Plus was funded by Health Canada's Chemicals Management Plan Research Fund. The 2D:4D component was funded by a research grant from the CIHR-Quebec Training Network in Perinatal Research (QTNPR). M.P. Vélez was supported by a CIHR Fellowship Award, and a QTNPR scholarship. P. Monnier is supported by the Research Institute of the McGill University Health Centre. W.D Fraser is supported by a CIHR Canada Research Chair. There are no conflicts of interest to declare.
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Affiliation(s)
- M P Vélez
- Department of Obstetrics and Gynecology, Kingston General Hospital, Queen's University, Kingston, Canada
| | - T E Arbuckle
- Population Studies Division, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Canada
| | - P Monnier
- Department of Obstetrics and Gynecology, McGill University Health Centre, Montreal, Canada
| | - W D Fraser
- Sainte-Justine University Hospital Research Centre, University of Montreal, Montreal, Canada Department of Obstetrics and Gynecology, University of Sherbrooke, Sherbrooke, Quebec, Canada
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Klimek M, Galbarczyk A, Nenko I, Jasienska G. Women with more feminine digit ratio (2D:4D) have higher reproductive success. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2016; 160:549-53. [DOI: 10.1002/ajpa.22989] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 03/09/2016] [Accepted: 03/15/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Magdalena Klimek
- Department of Environmental Health; Jagiellonian University Medical College; Grzegorzecka 20, 31-531 Krakow Poland
| | - Andrzej Galbarczyk
- Department of Environmental Health; Jagiellonian University Medical College; Grzegorzecka 20, 31-531 Krakow Poland
| | - Ilona Nenko
- Department of Environmental Health; Jagiellonian University Medical College; Grzegorzecka 20, 31-531 Krakow Poland
| | - Grazyna Jasienska
- Department of Environmental Health; Jagiellonian University Medical College; Grzegorzecka 20, 31-531 Krakow Poland
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Ellis L, Skorska MN, Bogaert AF. Handedness, sexual orientation, and somatic markers for prenatal androgens: Are southpaws really that gay? Laterality 2016; 22:157-180. [DOI: 10.1080/1357650x.2016.1151024] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Ellis L, Lykins A, Hoskin A, Ratnasingam M. Putative Androgen Exposure and Sexual Orientation: Cross-Cultural Evidence Suggesting a Modified Neurohormonal Theory. J Sex Med 2015; 12:2364-77. [PMID: 26663858 DOI: 10.1111/jsm.13070] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
INTRODUCTION According to neurohormonal theory, prenatal androgens are key determinants of sexual orientation. As a reputed marker for prenatal androgens, the 2D:4D finger length ratio has been used in more than a dozen studies to test the hypothesis that prenatal androgens influence sexual orientation. Findings have been very inconsistent. AIM The present study sought to retest the hypothesis that 2D:4D and sexual orientation are related is a manner consistent with neurohormonal theory. METHODS A 2D:4D measure (of the right hand) along with four additional somatic markers of androgen exposure (height, physical strength, muscularity, and athletic ability) with samples of college students in Malaysia (N = 2,058) and the United States (N = 2,511). The five androgen measures were factor analyzed, resulting in a two-factor solution: Factor 1 consisted of strength, muscularity, and athletic ability (the muscular coordination factor), and Factor 2 was comprised of the r2D:4D and adult height (the bone growth factor). MAIN OUTCOME MEASURES Sexual orientation was measured by asking each respondent the extent to which they were sexually attracted to males and the extent to which they were sexually attracted to females, both on 11-point scales. RESULTS When the countries and sexes were analyzed separately, neither the r2D:4D measure nor Factor 2 correlated with sexual orientation to significant degrees. Instead, it was the muscular coordination factor that correlated the best. Support was found for the hypothesis that prenatal androgens influence sexual orientation, but the nature of these influences was more complex than neurohormonal theory predicted. CONCLUSION A modified theory is needed and presented to accommodate the results from this study.
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Affiliation(s)
- Lee Ellis
- University of Malaya, Kuala Lumpur, Malaysia
| | - Amy Lykins
- University of New England, Armidale, NSW, Australia
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Apicella CL, Tobolsky VA, Marlowe FW, Miller KW. Hadza hunter-gatherer men do not have more masculine digit ratios (2D:4D). AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2015; 159:223-32. [PMID: 26354727 DOI: 10.1002/ajpa.22864] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 08/23/2015] [Accepted: 08/30/2015] [Indexed: 12/17/2022]
Abstract
OBJECTIVES The ratio between the length of the second and the length of the fourth digit (2D:4D) is sexually dimorphic such that males of many species possess a lower ratio than females, particularly in the right hand. Still, men and women often exhibit overlapping 2D:4D ranges and the ratio is highly variable between populations. In order to further explore populational variability, we chose to analyze 2D:4D in the Hadza, a population of hunter-gatherers living in Tanzania. MATERIALS AND METHODS Data were collected separately by two researchers over the course of three years (1998, 2001, 2006) from 152 adult participants (male: n = 76, female: n = 76). Independent samples t-tests were used to explore sex differences, paired samples t-tests were used to explore directional effects within each sex, and linear regression and one-way ANOVA were used to test possible age effects. RESULTS In none of the years, or pooled (n = 152), did we find evidence that adult men have a lower 2D:4D than adult women. If anything, the data suggest that women in this population have a significantly lower right hand 2D:4D than men (P < 0.001, d = 0.57). In contrast, left hand 2D:4D did not exhibit a sex difference (P = 0.862, d = 0.03). DISCUSSION These findings challenge the current view that lower 2D:4D in men is a uniform characteristic of our species. Cross-populational variance in 2D:4D may be related to known patterns of hormonal variation resulting from both genetic and environmental mechanisms, though this relationship merits further investigation.
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Affiliation(s)
- Coren L Apicella
- Department of Psychology, University of Pennsylvania, Philadelphia, PA, 19104
| | - Victoria A Tobolsky
- Department of Psychology, University of Pennsylvania, Philadelphia, PA, 19104.,Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, 02138
| | - Frank W Marlowe
- Division of Biological Anthropology, Department of Archaeology and Anthropology, Cambridge, CB2 3QG, UK
| | - Kathleen W Miller
- Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, 02138
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