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3.4 explain how cross-breeding experiments can identify the relative position of linked genes

explain how cross-breeding experiments can identify the relative position of linked genes

Example:
Genes A, B and C are linked. In a cross breeding experiment, ABC was crossed with abc and the percentages of recombinations were observed.

AB x ab
Results: AB and ab 85%
Ab and aB 15% (recombined through crossing over)
BC x bc

Results: BC and bc 95%
Bc and bC 5% (recombinations)

AC x ac

Results: AC and ac 90%
Ac and aC 10% (recombinations)

A and B are 15 units apart
A ________________15 _______________ B
B and C are 5 units apart
B ____5___C
A and C are 10 units apart
A ________10 _________C
The resulting map is:
A __________10__________C______5_____B