Why is RNase treatment used during DNA isolation?

Why is RNase treatment used during DNA isolation?

• A. To stain nucleic acids.
• B. To remove RNA contamination that can co-purify with DNA and interfere with analyses.
• C. To digest DNA.
• D. To promote RNA synthesis.

Answer: (B)

Removing RNA contamination is essential in DNA isolation because RNA can co-purify with DNA and remain in the sample, potentially confounding downstream analyses that assume a DNA-only material. RNase enzymes selectively degrade RNA, breaking it down so it can be washed away, leaving cleaner DNA for accurate quantification, PCR, sequencing, and other experiments. This is not about staining, it does not digest DNA, and it does not promote RNA synthesis—the purpose is to prevent RNA from skewing results and to improve overall sample purity.

Removing RNA contamination is essential in DNA isolation because RNA can co-purify with DNA and remain in the sample, potentially confounding downstream analyses that assume a DNA-only material. RNase enzymes selectively degrade RNA, breaking it down so it can be washed away, leaving cleaner DNA for accurate quantification, PCR, sequencing, and other experiments. This is not about staining, it does not digest DNA, and it does not promote RNA synthesis—the purpose is to prevent RNA from skewing results and to improve overall sample purity.