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Updated: Aug 21, 2026

Preparation of Meiotic Chromosome Spreads from Mouse Oocytes for Assessment of Synapsis and Recombination
Published on: July 18, 2025
Cytological studies of meiotic recombination in human males
1Department of Genetics and The Center for Human Genetics, Case Western Reserve University and University Hospitals of Cleveland, Cleveland VA Medical Center, Cleveland, OH 44106, USA. tjh6@po.cwru.edu
Abstract:
We combined immunostaining and fluorescence in situ hybridization (FISH) methodology to directly examine meiotic exchanges in over 2,000 pachytene stage spermatocytes from 25 individuals. Our results indicate that, on average, there are about 50 exchanges per cell and that, with the exception of the acrocentric chromosomes, all chromosome arms harbor at least one exchange. We also identified significant among-individual variation in the mean number of exchanges, with an approximate 20% difference between individuals with "low" and those with "high" exchange frequencies.
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