Which definition correctly captures the essence of epigenetics? (Use recall.)

• A. Epigenetics refers to chemical modifications to DNA or histone proteins that affect gene expression without altering the underlying DNA sequence.
• B. Epigenetics is the dietary practice of consuming specific epigenes to directly build proteins in the cytoplasm.
• C. Epigenetics is the process of permanent mutation of DNA sequences which leads to changes in gene expression across generations.
• D. Epigenetics describes changes in chromosome number (aneuploidy) that alter gene expression in developing tissues by physically deleting genes from the genome.

Answer: (A)