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Updated: Jul 9, 2026
08:20
Analysis of Apoptosis in Zebrafish Embryos by Whole-mount Immunofluorescence to Detect Activated Caspase 3
Published on: December 20, 2013
Cre activity causes widespread apoptosis and lethal anemia during embryonic development
L A Naiche1, Virginia E Papaioannou
1Department of Genetics and Development, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.
Genesis (New York, N.Y. : 2000)
|December 8, 2007
Summary
Cre recombinase activity alone can cause developmental defects, impacting gene expression studies. Researchers must include Cre-positive controls to avoid misattributing gene functions to Cre toxicity, ensuring accurate genetic analysis.
Area of Science:
- Genetics
- Developmental Biology
- Molecular Biology
Background:
- Cre-loxP recombination is a standard tool for genetic manipulation.
- Its application is crucial for temporal and tissue-specific gene deletion or activation.
Purpose of the Study:
- To investigate potential confounding phenotypes caused by Cre recombinase activity itself.
- To assess the necessity of Cre-positive controls in genetic studies.
Main Methods:
- Analysis of three established Cre alleles.
- Observation of developmental phenotypes in Cre-expressing embryos.
- Review of recently published literature for Cre-positive control inclusion.
Main Results:
- Cre activity alone induced significant developmental defects, including hematopoietic loss and increased apoptosis in embryonic tissues.
- Two of the examined Cre alleles exhibited these spurious phenotypes.
- A notable number of recent studies omitted essential Cre-positive controls.
Conclusions:
- Cre expression can lead to artifacts that complicate genetic analyses.
- The absence of Cre-positive controls in published studies may result in misinterpretation of gene function.
- Future research must incorporate Cre-positive controls to validate findings and avoid attributing Cre toxicity to targeted genes.
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