The relationship between chromatid interference and the mapping function.

E Sturt; C A Smith

doi:10.1159/000130714

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The relationship between chromatid interference and the mapping function.

E Sturt·C A Smith

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Abstract

A formula for a general mapping function involving only the number of chiasmata between two points on the chromosome and the average excess of four-stranded double exchanges over two-stranded double exchanges is derived. A formula is also given for deriving the proportion of three-stranded double exchanges after any given number of chiasmata; this is related to mapping for linkage with the centromere. It is shown that this proportion tends to a limit of 2/3 after a large number of chiasmata, whether or not chromatid interference is operating.

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E Sturt, C A Smith. 1976. The relationship between chromatid interference and the mapping function.. https://doi.org/10.1159/000130714

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