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J. ). University and D. Wilhelm, Comparative Medicine Branch, and Cellular and Molecular Pathology Branch for their services. This work was supported in part by the Intramural Research Program (ES102965) of the NIH, National Institute of Environmental Health Sciences in the U.S. The goat study was supported by Agence Nationale de la Recherche in France (ANR-16-CE14-0020). The human fetal gonads study was supported by l'Institut national de la santé et de la recherche médicale (Inserm), l'Université de Rennes 1 and l'Ecole des hautes études en santé publique (EHESP) in France. The study of red-eared slider turtle was supported by a grant, Integrative Bioinformatics Support Group

B. and Y. , designed the study, analyzed data, and wrote the paper. S.A.G performed bioinformatic analyses. F.C and E.L. analyzed RUNX1 expression in human fetal gonads. M.P. and E.P. analyzed RUNX1 expression in the goat

B. C. , E. L. , F. C. , M. P. , E. P. et al., analyzed Runx1 expression in the red-eared slider turtle