Genetics Dynamic mutations, imprinting, mitochondrial genetics

Question 1

Genomic imprinting is defined as […]

Answer 1

Genomic imprinting is defined as a phenomenon where the expression of a gene is dependent on the parent of origin

Question 2

genomic imprinting is set during […]

Answer 2

genomic imprinting is set during gametogenesis
Once imprinted, signal is set for life and maintained during subsequent DNA replication.

Parent of origin imprint is only erased and reset in cell that undergo gametogenesis

Question 3

Mechanism of trinucleotide mutation deletion or expansion

[…]

Answer 3

Question 4

mitochondrial genome are inherited from […]

Answer 4

mitochondrial genome are inherited from the mother
sperm mitochondrial are left at the tail (does not enter the ovum)

Question 5

mitochondrial disorders may present at any age.

however in general

[…] tend to present in childhood
[…] tend to present in late childhood or adult life

Answer 5

mitochondrial disorders may present at any age.

however in general

nuclear DNA mutations tend to present in childhood
mtDNA mutations tend to present in late childhood or adult life

Question 6

most common dynamic mutations are […]

Answer 6

most common dynamic mutations are trinucleotide repeat disease

Expansion mechanism (backward slippage causing insertion) more common than contraction.

Question 7

proteins that make up the mitochondrial respiratory chain are encoded by

[…]

Answer 7

proteins that make up the mitochondrial respiratory chain are encoded by

both nuclear and mitochondrial genome

(74 nuclear and 13 mitochondrial)

Question 8

Stable mutations (most mutations) […]

Dynamic mutations […]

Answer 8

Stable mutations (most mutations) remain stable when passed from one generation to another

Dynamic mutations are unstable when passed down from one generation to another (they change/are dynamic) (change in terms of expansion or contraction) (usually expansion)

eg. stable mutations

When a father has a certain mutation, does the child have the same mutation? or does it change?

Question 9

When do you suspect that a disease is due to problem in mitochondrial respiratory chain?
[…]

Answer 9

When do you suspect that a disease is due to problem in mitochondrial respiratory chain?
- when there is a disease that is progressive and involves multiple organ systems
- blood lactate is high

• when it fits on of the classic descriptions (which idk is what HAHHAHAH)