Molecular Biology/Genetics USMLE Step 1 Practice Question
A researcher studying metastatic breast cancer cells measures gene expression at multiple levels. She obtains tumor tissue samples and determines messenger RNA levels of HER2 receptor, then quantifies the corresponding HER2 protein expression in identical samples. Previous Western blot analysis showed no protein degradation. Which pair of laboratory techniques should she use sequentially for these two measurements to assess transcriptional and translational gene expression, respectively?
Answer choices
- AWestern blot then Southern blot
- BFlow cytometry then Western blot
- CNorthern blot then Western blotCorrect answer
- DNorthern blot then ELISA only for DNA
- ESouthern blot then Western blot
- FRT-PCR then immunohistochemistry
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