Extensions to Mendel Video Lessons

Video Thumbnail

Concept

Problem: Fruit color in a particular plant is controlled by a set of three QTLs (quantitative trait loci, or "polygenes") that work in an equal and additive manner. Each QTL has two alleles (i.e. A and a); each allele represented by a capital letter produces "one dose" of yellow pigment, while alleles represented with lower case letters do not produce any pigment at all. A trihybrid plant (A/a;B/b;C/c) is selfed. Assuming no effects of the environment, what proportion of the offspring will have thesame fruit color phenotype as the trihybrid parent?

FREE Expert Solution

Many phenotypes are characterized by a variation of multiple discrete characters. This is usually due to polygenic inheritance: two or more genes affecting a single phenotype. Such is the case of the genes in this problem. In this cross, there are eight possible gamete combinations for this corss: ABC, ABc, AbC, Abc, aBC, aBc, abC, and abc. A Punnet square using this number of gametes would produce 64 possible outcomes.

View Complete Written Solution
Problem Details

Fruit color in a particular plant is controlled by a set of three QTLs (quantitative trait loci, or "polygenes") that work in an equal and additive manner. Each QTL has two alleles (i.e. A and a); each allele represented by a capital letter produces "one dose" of yellow pigment, while alleles represented with lower case letters do not produce any pigment at all. A trihybrid plant (A/a;B/b;C/c) is selfed. Assuming no effects of the environment, what proportion of the offspring will have thesame fruit color phenotype as the trihybrid parent?

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Extensions to Mendel concept. You can view video lessons to learn Extensions to Mendel. Or if you need more Extensions to Mendel practice, you can also practice Extensions to Mendel practice problems.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor Puddephatt's class at Ryerson University.