Question

Errors can be introduced because of many reasons such as polymerase error or because of heterogeneity. Which of the statement holds true?

(a) The error caused because of polymerase is biased for the first position in the codon

(b) The error caused because of polymerase is evenly distributed on all the positions in the codon

(c) The error caused by sequence heterogeneity is mainly because of first position in the codon

(d) The error caused by sequence heterogeneity is evenly distributed on all the codon positions

The question was posed to me in unit test.

I want to ask this question from Precautions and Drawbacks topic in chapter Polymerase Chain Reaction of Genetic Engineering

Answer 1

The correct choice is (b) The error caused because of polymerase is evenly distributed on all the positions in the codon

The explanation: The error caused by polymerase whether due to template change or not, it is always distributed evenly over all the codon positions. If the error is caused by sequence heterogeneity is concentrated on the third codon position. It generally doesn’t leads to amino acid substitution.