20 - Epigenetics

Question 1

How can chromatin structure be remodeled?

Answer 1

Question 2

Explain how DNA methylation represses transcription. Why is this important for cell replication?

Answer 2

Question 3

How does epigenetic modification impact control in gene expression of DNA? Can it affect RNA?

Answer 3

Question 4

How does X Chromosome inactivitation occur via chromatin remodeling? Why is this important?

Answer 4

Question 5

Are epigenetic marks passed down to progeny? Why or why not?

Answer 5

Epigenetic Marks are Erased in Primordial Germ Cells & Post Fertilized Eggs
DNA De-methylation is both active (“DNA de-methlyase” in male genome) and passive (cell division in absence of methylase in female genome)
However, Imprinting (image) is also a consideration:

Question 6

What is Angelman Syndrome? What are its hallmarks? What is its genetic basis?

Answer 6

Question 7

What is Prader-Willi Syndrome? What are its hallmarks? What is its genetic basis?

Answer 7

Question 8

What is Beckwith-Wiedemann Syndrome? What are its hallmarks? What is its genetic basis?

Answer 8

Question 9

What is Russel-Silver Syndrome? What are its hallmarks? What is its genetic basis?

Answer 9

Question 10

What is Rett Syndrome? What are its hallmarks? What is its genetic basis?

Answer 10

NOT IMPRINTING

Question 11

What are some common syndromes associated with imprinting in epigenetics?

Answer 11

Rett is not imprinting based, but closely related

Rett:
* >95% from de novo mutations in MeCP2 on X chr
* MeCP2 is DNA methyl binding protein controls gene expression by direct binding and chromatin remodeling
* Rett variants from mutations in FOXG1(chr 14) and CDKL5 (chr X)

Question 12

Explain.

Answer 12