Chapter 18, Problem 3Q

Summary Introduction

To explain:

The mutagenic chain reaction (MCR) method would result in a rapid increase in the frequency of the mutated alleles in the population if the flies were released to the wild.

Introduction:

The MCR is a method, which converts heterozygous mutation to homozygous mutation. This method includes CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas9 genome editing technology.

In the given case, researchers wanted to produce malaria resistance mosquitoes by using gene knockout method. In this method, only one allele is mutated, which do not result in a rapid spread of malaria resistance. There was a need for method that can mutate two alleles together. Thus, researchers used MCR to produce flies with the homozygous mutation. They used CRISPR technology to convert heterozygous mutations to homozygous ones in the model organism Drosophila melanogaster. The CAS9 enzyme was used to cut body color gene carried on the X chromosome. The mutated genes are replicated by fly’s deoxyribonucleic acid (DNA).