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Updated: Jul 6, 2026
08:01
Identification of Homologous Recombination Events in Mouse Embryonic Stem Cells Using Southern Blotting and Polymerase Chain Reaction
Published on: November 20, 2018
A mitotic recombination system for mouse chromosome 17.
1Institute of Developmental Biology and Molecular Medicine, School of Life Science, Fudan University, Shanghai 200433, China.
Summary
Researchers developed a Cre/LoxP system in mice for genetic mosaic analysis. This system enables accurate detection of mitotic recombination events in live cells, particularly within the immune system.
Area of Science:
- Genetics
- Molecular Biology
- Immunology
Background:
- Mitotic recombination is a key genetic technique for mosaic analysis in model organisms.
- Mouse models require robust recombination systems for individual chromosomes and sensitive detection methods.
Purpose of the Study:
- To establish a Cre/LoxP-mediated recombination system in mice for mosaic analysis of chromosome 17.
- To evaluate the efficiency and reproducibility of this system in detecting mitotic recombination in somatic tissues.
Main Methods:
- Utilized a Cre/LoxP system for germ-line recombination induction in mice.
- Assessed mitotic recombination in B and T lymphocytes using surface markers and fluorescent-activated cell sorting (FACS).
Main Results:
- Achieved approximately 9% germ-line recombination frequency in progeny.
- Demonstrated a reproducible mitotic recombination frequency of 0.5-1.0% in lymphoid progenitors induced by lineage-specific Cre.
- Enabled simple and accurate detection and isolation of recombination events in live cells.
Conclusions:
- The established Cre/LoxP system provides an effective tool for mosaic analysis of chromosome 17 in mice.
- This system offers a reliable method for studying mitotic recombination in the immune system, facilitating mutagenesis studies.
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