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Highly variable penetrance of abnormal phenotypes in embryonic lethal knockout mice
Robert Wilson1, Stefan H Geyer2, Lukas Reissig2
1The Francis Crick Institute, London, UK.
Wellcome Open Research
|December 21, 2016
Summary
Identifying essential genes in mouse embryonic development aids in understanding human developmental disorders. Ablating lethal genes reveals crucial roles in development and potential links to human congenital abnormalities.
Area of Science:
- Developmental Biology
- Genetics
- Medical Genetics
Background:
- Identifying essential genes in mouse embryonic development is key to understanding human developmental disorders.
- Characterizing gene ablation effects in mouse embryos is crucial for uncovering developmental roles and human congenital abnormality correlations.
Purpose of the Study:
- To catalog morphological defects in mouse embryos with lethal or subviable gene mutations.
- To investigate the role of specific genes in embryonic development and their potential links to human diseases.
Main Methods:
- Comprehensive imaging of 220 homozygous mutant and 114 wild-type mouse embryos at E14.5.
- Analysis of 42 lethal and subviable gene lines within the Deciphering the Mechanisms of Developmental Disorders (DMDD) program.
Main Results:
- Nearly all mutant embryos exhibited multiple abnormal phenotypes affecting most organ systems.
- Prevalent defects included subcutaneous edema, cardiac and great vessel malformations, forebrain abnormalities, eye musculature defects, and hypoglossal nerve abnormalities.
- Phenotypes within each mutant line displayed distinct yet overlapping patterns among individual embryos.
Conclusions:
- A significant finding is the high variability in phenotype penetrance, even with profound malformations within a single mutant line.
- These variable penetrance findings present challenges for identifying human disease correlates.
- The study highlights the complexity of gene function in embryonic development and its relevance to human health.
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