Question

A geneticist wants to isolate mutants in mice that are defective in nucleotide excision repair (NER) but is unable to do biochemical analysis on the NER system so much use some other method to identify putative NER mutations. Which of the following would most likely be useful in identifying NER mutations in mice?

Answer 1

To identify NER mutations in mice, the geneticist could monitor UV sensitivity, employ reverse genetics with reporter genes to identify the affected NER components, or use SNP analysis to correlate genetic variations with NER defects.

Step-by-step explanation:

To identify NER mutations in mice without biochemical analysis, the geneticist could utilize several strategies. One effective approach could be monitoring the sensitivity of mice to UV light since NER is responsible for repairing UV-induced DNA damage such as thymine dimers. Mice with defective NER pathways might show increased sensitivity or develop more DNA damage than normal under UV exposure.

Another approach could be using reverse genetics techniques. By systematically silencing or mutating genes involved in the NER pathway and observing the resulting phenotypes, researchers can identify which genes contribute to the NER function. Reporter genes such as lacZ or GFP could be used as indicators for the functionality of NER components when subjected to DNA-damaging agents.

Additionally, techniques such as SNP analysis can be utilized to scan for genetic variations that correlate with defective NER activity. This method relies on understanding that certain mutations at the nucleotide level can have phenotypic consequences, and identifying such mutations could lead to the identification of genes involved in NER.