Problem 7 Considering Figure 213 if you had a homozygous dou

(Problem 7) Considering Figure 2-13, if you had a homozygous double mutant m3 m3 m5 m5, do you expect it to be mutant in phenotype? (Note: This line would have two mutant sites in the same coding sequence.)
	No, because the two mutations cancel each other out, generating a normal phenotype. No, because the m5 mutation would suppress the effects of the m3 mutation, generating a normal phenotype. Yes, because the active-site mutation, m3, is sufficient to generate a mutant phenotype. Yes, in fact the presence of both mutations would lead to a more extreme mutant phenotype.

DNA Components of protein active site Promoter Intron 5 Exon Exon Active site m2 Protein m4 m5 o mutant site m3 o Figure 2.13 introduction to Generic Andlysis.Eleventh Edition 2015 WHL Freeman and Company 3 Wildtype m1: null m2: null m3: null m4: leaky m5: silent m6: null

Solution

The answer is Yes,

This double mutant m3/m3 m5/m5 would generate null mutation

Because m3 mutation changes the exon sequence.

Since, the m5 mutation is silent, the homozygous double mutant m3/m3 m5/m5 would have the same mutant phenotype as an m3/m3 double mutant.

A null mutation in a gene is defined as a mutation that leads to the production of a nonfunctional enzyme or no enzyme at all.