Sex reversal by estradiol in three reptilian orders

Bull, James J.; Gutzke, William H. N.; Crews, David

doi:10.1016/0016-6480(88)90117-7

Cited by 152 publications

(81 citation statements)

References 8 publications

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“…Further, they * -3 --I hi found that -some of the EB-treated turtle embryos exhibited hypertrophied oviducts (44). As in turtles, alligator eggs incubated at a male-producing temperature and treated with 100 pg or 300 pg EB/egg induced sex reversal in 100% of the eggs so treated (41) E2 and T indicate that no turtle hatchling from Lake Apopka produces a normal androgen synthesis pattern (Gross and Guillette, unpublished data). Reptiles represent excellent models for determining the extent of estrogenic xenobiotic contamination in an ecosystem owing to the apparent lability of sex determination in response to the presence of estrogen or estrogenlike compounds.…”

Section: Discussionmentioning

confidence: 97%

“…Specifically, estrogen treatment of alligator (41) and turtle (42)(43)(44) eggs incubated at male-producing temperatures can cause sex reversal and the production of apparently normal females. Crews et al (44) found that estradiol benzoate (EB) or an estrogen agonist (R2858) were equally effective in inducing turtle embryos to develop as females when eggs were incubated at maleproducing temperatures.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Developmental abnormalities of the gonad and abnormal sex hormone concentrations in juvenile alligators from contaminated and control lakes in Florida.

Guillette

Gross

Masson

et al. 1994

Environ Health Perspect

997

436

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Section: Discussionmentioning

confidence: 97%

Section: Discussionmentioning

confidence: 99%

Developmental abnormalities of the gonad and abnormal sex hormone concentrations in juvenile alligators from contaminated and control lakes in Florida.

Guillette

Gross

Masson

et al. 1994

Environ Health Perspect

997

436

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“…Application of exogenous estrogenic compounds typically feminizes reproductive tissues, and overrides the influence of incubation temperature on sex determination under TSD (Bull et al, 1988;Wibbels et al, 1991b;Rhen and Lang, 1994;Devlin and Nagahama, 2002;Elf, 2004). In addition, Fadrozole has previously been shown to induce male development by blocking the aromatization of androgens to estrogens in many taxa (Piferrer et al, 1994;Wibbels and Crews, 1994;Chardard and Dournon, 1999;Warner et al, 2005).…”

Section: Discussionmentioning

confidence: 99%

Exogenous application of estradiol to eggs unexpectedly induces male development in two turtle species with temperature-dependent sex determination

Warner¹,

Addis²,

Du³

et al. 2014

General and Comparative Endocrinology

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Steroid hormones affect sex determination in a variety of vertebrates. The feminizing effects of exposure to estradiol and the masculinizing effects of aromatase inhibition during development are well established in a broad range of vertebrate taxa, but paradoxical findings are occasionally reported. Four independent experiments were conducted on two turtle species with temperature-dependent sex determination (Chrysemys picta and Chelydra serpentina) to quantify the effects of egg incubation temperature, estradiol, and an aromatase inhibitor on offspring sex ratios. As expected, the warmer incubation temperatures induced female development and the cooler temperatures produced primarily males. However, application of an aromatase inhibitor had no effect on offspring sex ratios, and exogenous applications of estradiol to eggs produced male offspring across all incubation temperatures. These unexpected results were remarkably consistent across all four experiments and both study species. Elevated concentrations of estradiol could interact with androgen receptors or inhibit aromatase expression, which might result in relatively high testosterone concentrations that lead to testis development. These findings add to a short list of studies that report paradoxical effects of steroid hormones, which addresses the need for a more comprehensive understanding of the role of sex steroids in sexual development. KeywordsAromatase inhibitor, Chelydra serpentina, Chrysemys picta, Environmental sex determination, Sex steroids, Sexual differentiation Disciplines Aquaculture and Fisheries | Ecology and Evolutionary Biology | Other Ecology and Evolutionary Biology | Population Biology | ZoologyComments NOTICE: this is the author's version of a work that was accepted for publication in General and Comparative Endocrinology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in General and Comparative Endocrinology, 206 (2014) ABSTRACTSteroid hormones affect sex determination in a variety of vertebrates. The feminizing effects of exposure to estradiol and the masculinizing effects of aromatase inhibition during development are well established in a broad range of vertebrate taxa, but paradoxical findings are occasionally reported. Four independent experiments were conducted on two turtle species with temperature-dependent sex determination (Chrysemys picta and Chelydra serpentina) to quantify the effects of egg incubation temperature, estradiol, and an aromatase inhibitor on offspring sex ratios. As expected, the warmer incubation temperatures induced female development and the cooler temperatures produced primarily males. However, application of an aromatase inhibitor had no effect on offspring sex ratios, and exogenous applications of estradiol to eggs produced ...

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“…Egg injections have been successfully employed in avian studies with various contaminants [8,[19][20][21][22]. However, injection of reptilian eggs has frequently resulted in very high embryonic mortality rates ranging from approximately 44 to 79% [23][24][25][26], suggesting that the reptilian egg is more sensitive to the physical damage associated with injection relative to the avian egg. Schnars and colleagues [27] reported the highest hatching success (61%) after injection in snapping turtle eggs harvested directly from the oviducts of adult females prior to laying, which is a much lower success rate than in studies employing topical dosing techniques.…”

Section: Introductionmentioning

confidence: 99%

Experimental exposure of eggs to polybrominated diphenyl ethers BDE‐47 and BDE‐99 in red‐eared sliders (Trachemys scripta elegans) and snapping turtles (Chelydra serpentina) and possible species‐specific differences in debromination

Eisenreich¹,

Rowe²

2012

Enviro Toxic and Chemistry

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Abstract-Polybrominated diphenyl ethers (PBDEs) are a bioaccumulative, persistent, and toxic class of flame retardants that can potentially impact turtles in natural habitats via exposure through maternal transfer. To simulate maternal transfer in the present study, PBDE congeners BDE-47 and BDE-99 were topically applied to the eggshell and were allowed to diffuse into the egg contents of the redeared slider (Trachemys scripta elegans) and snapping turtle (Chelydra serpentina). Eggs were topically dosed over 8 d to achieve a target concentration of 40 ng/g in the egg contents. Transfer efficiency was higher for BDE-47 than for BDE-99 in the red-eared sliders (25.8 AE 1.9% vs 9.9 AE 1.1%) and snapping turtles (31.3 AE 1.6% vs 12.5 AE 1.4%), resulting in greater BDE-47 and lower BDE-99 egg content concentrations relative to the 40 ng/g target. However, only 25.8 and 31.3% of the total BDE-47 and 9.9 and 12.5% of the total BDE-99 dose applied could be accounted for in the red-eared slider and snapping turtle egg contents, respectively. Additionally, increased BDE-47 in red-eared slider egg contents dosed with only BDE-99 indicate that BDE-99 might have been debrominated to BDE-47. The efficacy of topical dosing for administering desired embryonic exposures is clearly affected by the chemical properties of the applied compounds and was more successful for BDE-47 in both species. Environ. Toxicol. Chem.

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Sex reversal by estradiol in three reptilian orders

Cited by 152 publications

References 8 publications

Developmental abnormalities of the gonad and abnormal sex hormone concentrations in juvenile alligators from contaminated and control lakes in Florida.

Developmental abnormalities of the gonad and abnormal sex hormone concentrations in juvenile alligators from contaminated and control lakes in Florida.

Exogenous application of estradiol to eggs unexpectedly induces male development in two turtle species with temperature-dependent sex determination

Experimental exposure of eggs to polybrominated diphenyl ethers BDE‐47 and BDE‐99 in red‐eared sliders (Trachemys scripta elegans) and snapping turtles (Chelydra serpentina) and possible species‐specific differences in debromination

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