What is the goal of reverse genetics?

• A. To clone genes
• B. To determine the role of a gene through mutation
• C. To improve the efficiency of gene expression
• D. To identify genes responsible for diseases

Answer: (B)

The goal of reverse genetics is to determine the role of a gene through mutation. This approach starts with a known gene and then investigates its function by creating specific mutations or deletions in that gene. By observing the phenotypic consequences of these mutations in an organism, researchers can infer the gene's function and its role in biological processes. This is an essential strategy in functional genomics, allowing scientists to connect genes to their respective traits or diseases, ultimately leading to a deeper understanding of gene function in vivo.

In contrast, cloning genes primarily relates to producing multiple copies of a given DNA sequence, which is not the main focus of reverse genetics. Improving the efficiency of gene expression pertains to optimizing how genes are expressed in an organism but doesn’t directly involve determining gene function via mutational analysis. Identifying genes responsible for diseases is often a goal of other approaches like forward genetics, which begins with particular phenotypes and seeks to find the underlying genetic causes. Thus, while identifying disease-related genes can be a secondary outcome of reverse genetics, it does not encapsulate the primary aim of this approach, which is gene function elucidation through mutagenesis.