Question

For each, whether they illustrate forward, or reverse, genetic approaches, and explain why you made that choice.

A.Your graduate student read a paper in which mutations in a specific antioxidant gene leads to resistance to the biological effects of cocaine in mice. She decides to use Cas-CRISPR to make a targeted mutation in the Drosophila homolog of this gene and examine the effects of cocaine on the resulting mutant flies. Is this a forward or reverse genetic approach?

B. Your graduate student has performed a genetic screen and isolated twenty mutations that lead to resistance to the drug PCP in flies. She proceeds to clone and sequence the mutated genes. Is this a forward or reverse genetic approach?

Answer 1

A. answer- This illustrate forward genetic approach because single specific antioxidant gene underlies a specific mutant phenotype is targeted to study the effects of cocaine on the resulting mutant flies by making targeted mutation in the Drosophila homolog of this gene through Cas-CRISPR. This study is based on single target gene rather than whole genome screening, therefore this study is forward genetics approach to find the genetic basis of a phenotype .

B. answer- This study is based on genetic screen which resulted inn isolation of twenty mutations that lead to resistance to the drug PCP in flies. This study is reverse gentics approach because it wll identify the phenotype based on mutation screening gained through whole genome approach.

Reverse genetics is based on sequence information as retrieved from genome and transcript profiling projects and investigate to gain insight into the unknown function by selecting for mutation.