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Updated: Jul 5, 2026
06:18
Frequency and Distribution of Crossovers in Caenorhabditis elegans Meiosis by SNP Genotyping using Real-time PCR
Published on: July 11, 2025
Variation in crossover interference levels on individual chromosomes from human males
Jie Lian1, Yimeng Yin, Maria Oliver-Bonet
1Hefei National Laboratory for Physical Sciences, Microscale 2 School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China.
Human Molecular Genetics
|May 27, 2008
Summary
Human crossover interference varies across the genome and between individuals. Chromosome structure anomalies, like gaps and splits, significantly alter crossover interference levels in males.
Area of Science:
- Genetics
- Cell Biology
- Human Reproduction
Background:
- Homologous recombination generates crossovers (COs) crucial for meiotic chromosome segregation.
- COs exhibit interference, leading to spacing, with strong positive interference observed in humans.
- The extent and variation of human CO interference remain largely uncharacterized.
Purpose of the Study:
- To analyze variations in CO interference across the human genome and among individuals.
- To investigate the relationship between chromosome structure and CO interference levels.
Main Methods:
- Immunofluorescence and fluorescence in situ hybridization on testicular biopsies from 10 men.
- Direct identification of CO frequency and location in pachytene spermatocytes.
- Gamma model fitting to estimate CO interference strength from inter-CO distance distributions.
Main Results:
- Positive interference among COs was confirmed in human males, with inter-arm interference stronger than intra-arm.
- Interference was observed to operate across centromeres.
- Significant inter-individual and inter-chromosomal variations in interference levels were found, with smaller chromosomes showing stronger interference.
- Chromosome 9 gaps and splits influenced CO interference levels through cis and trans effects.
Conclusions:
- Human CO interference levels exhibit significant variation across the genome and between individuals.
- Anomalies in chromosome synapsis, such as gaps and splits, play a crucial role in modulating CO interference in human males.
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