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Mouse Oocyte Microinjection, Maturation and Ploidy Assessment
Published on: July 23, 2011
Chromosome transfer in mature oocytes
Masahito Tachibana1, Michelle Sparman, Shoukhrat Mitalipov
1Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, USA.
Nature Protocols
|June 12, 2010
Summary
This study details a method for transferring spindle-chromosomal complexes between oocytes, enabling the creation of reconstructed eggs with nuclear DNA from one female and cytoplasmic factors from another for reproductive applications.
Area of Science:
- Reproductive Biology
- Cell Biology
- Developmental Biology
Background:
- Oocyte quality is crucial for successful fertilization and embryonic development.
- Mitochondrial DNA (mtDNA) mutations can cause inherited diseases.
- Cytoplasmic defects in oocytes can lead to infertility.
Purpose of the Study:
- To establish a protocol for spindle-chromosomal complex transfer between oocytes.
- To create reconstructed oocytes with nuclear genetic material from one donor and cytoplasmic components from another.
- To explore potential applications in reproductive medicine and genetic therapies.
Main Methods:
- Isolation and visualization of spindle-chromosomal complexes using polarized microscopy.
- Extraction of complexes into karyoplasts.
- Fusion of karyoplasts with enucleated recipient oocytes (cytoplasts).
- Developmentally competent reconstructed oocytes are produced.
Main Results:
- Successful transfer of spindle-chromosomal complexes between oocytes.
- Generation of reconstructed oocytes containing nuclear DNA from one female and cytoplasmic factors (including mtDNA) from another.
- Demonstrated applicability in monkey, mouse, and human oocytes.
- Protocol completion within 2 hours.
Conclusions:
- This technique allows for the creation of developmentally competent oocytes for fertilization, embryonic stem cell production, or healthy offspring.
- Potential for mitochondrial gene replacement therapy to prevent transmission of mtDNA diseases.
- Offers a therapeutic avenue for infertility stemming from oocyte cytoplasmic defects.
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