Name: Incomplete Linkage in Drosophila
Uploaded: 2019-07-19
Duration: 8 min 39 s
Description: Completely linked genes show zero recombination. What about incomplete linkage? How can we predict the exact number of recombinants in a progeny? Learn about...

Question

Explain the experiment of Bateson and Punnet.

Accepted Answer

While performing a dihybrid cross, Bateson and Punnett observed the genes were not assorted independently and deviated from normal dihybrid ratio of 9:3:3:1. For their experiment, they crossed pea plant bearing blue flower (BB) and long pollen (LL) with the plant bearing red flower (bb) and round pollen (II). All the F₁ individuals (BbLl) had a blue flower and long pollen. When F₁ progeny was test crossed with homozygous recessive plants, instead of 1:1:1:1 ratio, they got 7:1:1:7 ratio. They called this phenomenon as coupling or tendency of the dominant allele to remain together.

In another set of the experiment, they crossed blue flower (BB) and round pollen (II) with the plant bearing red flower (bb) and long pollen (LL). When F₁progeny was test crossed, instead of 1:1:1:1 ratio, they got 1:7:7:1 ratio. They called this phenomenon as repulsion. They called the whole phenomenon as coupling and repulsion and later it was found that this phenomenon is due to linkage of the genes.

Explain the experiment of Bateson and Punnet.

Important Questions on Chromosomal Basis of Inheritance

Learn and Prepare for any exam you want !