Epigenetics Flashcards
the genome is fixed, the epigenome is not fixed, is this true or false
True
The epigenome can be affected by external factors - True or false
True
Identical twins have identical genomes but can have different epigenomes - true or false
True
what is the protein the DNA is wrapped around called
histones
what is DNA methylation
Enzymes can methylate the DNA itself. Methylated genes tend to not be expressed and once methylated future daughter cells become methylated after replication.
Histone modification
Methylation and demethylation of histones turns genes”off” and “on,”.If turned off the DNA wraps tighter around the histones preventing transcription factors access to the DNA. If turned on the DNA is loosened and the DNA/gene is made accessible
what are Proto-oncogenes
Proto-oncogenes (pre-cancerous name) are genes which produce proteins to help cells grow and divide. If this gene mutates it can become permanently turned on. If this happens, the cell then grows out of control, which can lead to cancer.
what are histones and what do they do
DNA is coiled around a protein known as Histones; histones are the primary section that makes up chromatin. The DNA and Histones are covered with chemical tags (This layer is called the epigenome).
Name three examples of factors that might affect your epigenome?
Diet, stress and environmental pollutants
What does the Epigenome do?
the epigenetic tags respond to signals in the outside environment, and the Epigenome adjusts certain genes to react to the environment.
How can tumour suppressor genes cause cancer?
tumour suppressor genes, which halt cell division, fix DNA errors, and warn cells when to terminate (apoptosis). Whenever a gene malfunctions, such as a mutation, cell division may rapidly grow out of control as the gene is ‘shut off.’
