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[2] Zheng Z, Cohn MJ. Developmental basis of sexually dimorphic digit ratios. Proc Natl Acad Sci USA, 2011; 108, 16289-94. doi:  10.1073/pnas.1108312108
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[4] Oyeyemi BF, Iyiola OA, Oyeyemi AW, et al. Sexual dimorphism in ratio of second and fourth digits and its relationship with metabolic syndrome indices and cardiovascular risk factors. J Res Med Sci, 2014; 19, 234-9. http://www.ncbi.nlm.nih.gov/pubmed/24949031
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[8] Klimek M, Galbarczyk A, Nenko I, et al. Digit ratio (2D:4D) as an indicator of body size, testosterone concentration and number of children in human males. Ann Hum Biol, 2014; 41, 518-23. doi:  10.3109/03014460.2014.902993
[9] García-Cruz E, Huguet J, Piqueras M, et al. Second to fourth digit ratio, adult testosterone level and testosterone deficiency. BJU International, 2012; 109, 266-71. doi:  10.1111/j.1464-410X.2011.10249.x
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[11] Klimek M, Galbarczyk A, Colleran H, et al. Digit ratio (2D:4D) does not correlate with daily 17beta-estradiol and progesterone concentrations in healthy women of reproductive age. Am J Hum Biol, 2015; 27, 667-73. doi:  10.1002/ajhb.22717
[12] Hönekopp J, Bartholdt L, Beier L, et al. Second to fourth digit length ratio (2D:4D) and adult sex hormone levels:New data and a meta-analytic review. Psychoneuroendocrinology, 2007; 32, 313-21. doi:  10.1016/j.psyneuen.2007.01.007
[13] Faul F, Erdfelder E, Buchner A, et al. Statistical power analyses using G*Power 3.1:tests for correlation and regression analyses. Behav Res Methods, 2009; 41, 1149-60. doi:  10.3758/BRM.41.4.1149
[14] Oyeyemi BF, Ologunde CA, Olaoye AB, et al. FTO Gene Associates and Interacts with Obesity Risk, Physical Activity, Energy Intake, and Time Spent Sitting:Pilot Study in a Nigerian Population. Journal of obesity, 2017; 2017. doi: 10.1155/2017/3245270.
[15] Manning JT, Fink B. Digit ratio (2D:4D), dominance, reproductive success, asymmetry, and sociosexuality in the BBC Internet Study. Am J Hum Biol, 2008; 20, 451-61. doi:  10.1002/(ISSN)1520-6300
[16] Hönekopp J, Voracek M, Manning JT. 2nd to 4th digit ratio (2D:4D) and number of sex partners:Evidence for effects of prenatal testosterone in men. Psychoneuroendocrinology, 2006; 31, 30-7. doi:  10.1016/j.psyneuen.2005.05.009
[17] Kelly DM, Jones TH. Testosterone and obesity. Obes Rev, 2015; 16, 581-606. doi:  10.1111/obr.2015.16.issue-7
[18] Moon H, Choi I, Kim S, et al. Cross-sectional association between testosterone, sex hormone-binding globulin and metabolic syndrome:The Healthy Twin Study. Clin Endocrinol, 2017; 87, 523-531. doi:  10.1111/cen.2017.87.issue-5
[19] Reue K. Sex differences in obesity:X chromosome dosage as a risk factor for increased food intake, adiposity and co-morbidities. Physiol Behav, 2017; 176, 174-82. doi:  10.1016/j.physbeh.2017.02.040