Nature vs Nurture

• What is epigenetics?

  Changes to an organism’s phenotype resulting from modifications to gene expression
• How does DNA methylation affect gene expression?


  It modifies the expression of a gene by adding methyl groups to nucleotides
• What are histone-modifying enzymes known as?

  Histone methyltransferases (HMT)
• What happens during histone modification?


  Methyl groups are added to histone tails, modifying DNA wrapping
• How does tighter DNA wrapping around histones affect gene transcription?

  It makes it more difficult for the genes to be transcribed
• What is the effect of less tightly packed DNA around histones?


  It makes the genes easier to transcribe and more likely to be expressed