Molecular Biology/Genetics USMLE Step 1 Practice Question
A scientist exposes a culture of a bacterium with minimal nutritional requirements to a chemical mutagen, then streaks out the bacteria on plates filled with a complex medium supplemented with all necessary nutrients. When the bacteria begin growing, she isolates individual colonies and tests each one for the ability to grow on a minimal medium. Cells derived from colonies unable to grow on a minimal medium are considered mutants, and their genome is sequenced. In one case, she finds that a 2-nucleotide segment of DNA has been deleted. This deletion would most likely give rise to which of the following?
Answer choices
- AConservative mutation
- BMissense mutation
- CNonsense mutation
- DSilent mutation
- EFrameshift mutationCorrect answer
- FPoint mutation
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