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Dissection of Larval Zebrafish Gonadal Tissue
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Sex-specific embryonic origin of postnatal phenotypic variability
R Laguna-Barraza1, P Bermejo-Álvarez, P Ramos-Ibeas
1Departamento de Reproducción Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Avda Puerta de Hierro no. 12, Local 10, Madrid 28040, Spain.
Reproduction, Fertility, and Development
|December 19, 2012
Summary
Early embryo development shows plasticity, but environmental factors can cause sex-specific epigenetic changes, impacting adult health and birth weight. Understanding this sexual dimorphism is key to early health programming.
Area of Science:
- Developmental biology
- Epigenetics
- Reproductive science
Background:
- Early life environmental exposures can lead to long-term health issues, influencing neonatal and adult biology.
- Birth weight, a predictor of metabolic syndrome risk, is significantly determined before blastocyst formation, with minimal genetic or environmental influence at that stage.
- Adult body weight programming is linked to energy-dependent processes during the pronuclear stage in mice.
Purpose of the Study:
- To review current knowledge on natural phenotypic variation driven by epigenetic mechanisms in early embryo development.
- To explore mechanisms of sex-specific phenotypic changes during early embryogenesis.
- To understand how these changes influence sex ratio adjustments and long-term adult health consequences.
Main Methods:
- Literature review of studies on preimplantation development, epigenetics, and environmental influences.
- Analysis of sex-specific transcriptional and epigenetic regulation in early embryos (e.g., bovine blastocysts).
- Examination of data linking in vitro culture to abnormal fetal outcomes.
Main Results:
- Preimplantation embryos exhibit plasticity for survival but environmental insults can have adverse consequences.
- Sex-specific transcriptional and epigenetic regulation occurs in early embryos, influencing developmental trajectories.
- Environmental factors can impact preimplantation development in a sex-specific manner, affecting sex ratios and adult health.
Conclusions:
- Environmental exposures during early development, including in vitro culture, can lead to detrimental, sex-specific health outcomes.
- Understanding embryo sexual dimorphism and epigenetic programming is crucial for identifying early mechanisms of environmental insult response.
- This knowledge aids in comprehending the origins of sex-specific health disparities and optimizing early life health strategies.
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