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Updated: Jul 5, 2026

Frequency and Distribution of Crossovers in Caenorhabditis elegans Meiosis by SNP Genotyping using Real-time PCR
Published on: July 11, 2025
On the "NPD ratio" as a test for crossover interference
1Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA. fstahl@uoregon.edu
Abstract:
The "NPD ratio," widely used by yeast geneticists, is of limited applicability and is prone to falsely indicate significant crossover interference in a chi-square test. A simple, better chi-square test for interference in two-factor crosses is described.
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