In a DNA microarray experiment comparing cancer cells to normal cells, the cancer sample is labeled with a red fluorescent dye and the normal sample with a green fluorescent dye. A spot on the array appears red. What does this indicate?

• A The gene is deleted in the normal sample
• B The gene is overexpressed in the normal sample
• C The gene is equally expressed in both samples
• D The gene is overexpressed in the cancer sample ✓

Explanation

In two-color microarrays, a red spot indicates the gene is overexpressed in the cancer sample compared to the normal control. Green indicates overexpression in the normal sample. Yellow indicates equal expression in both samples due to equal mixing of the dyes.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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