Which epigenetic mechanism can be inherited across generations without changing the DNA sequence?

Which epigenetic mechanism can be inherited across generations without changing the DNA sequence?

• A. DNA sequence mutation
• B. Ribosome biogenesis
• C. DNA methylation patterns and histone modifications
• D. Protein folding

Answer: (C)

Epigenetic inheritance involves heritable changes in gene expression without altering the DNA sequence. The mechanisms that can be passed from one generation to the next include DNA methylation patterns and histone modifications. DNA methylation adds methyl groups to cytosines, often silencing genes, while histone modifications change how tightly DNA is wound and thus how accessible genes are to transcription. These marks can be copied each time DNA is replicated and, in some cases, survive the development of gametes, transmitting regulatory information to offspring without any change to the underlying sequence. That's why this option is the best choice. In contrast, a DNA sequence mutation changes the actual nucleotide sequence, which is not an epigenetic mechanism. Ribosome biogenesis and protein folding are essential cellular processes, not modes of inherited gene regulation.

Epigenetic inheritance involves heritable changes in gene expression without altering the DNA sequence. The mechanisms that can be passed from one generation to the next include DNA methylation patterns and histone modifications. DNA methylation adds methyl groups to cytosines, often silencing genes, while histone modifications change how tightly DNA is wound and thus how accessible genes are to transcription. These marks can be copied each time DNA is replicated and, in some cases, survive the development of gametes, transmitting regulatory information to offspring without any change to the underlying sequence. That's why this option is the best choice. In contrast, a DNA sequence mutation changes the actual nucleotide sequence, which is not an epigenetic mechanism. Ribosome biogenesis and protein folding are essential cellular processes, not modes of inherited gene regulation.