Genetics week 6 + clinical info Flashcards
1
Q
What is another way to write mitochondrial DNA
A
- mtDNA
2
Q
Where is mitochondrial DNA inheritied from
A
- Maternal line
3
Q
What does the mitochondrial encode and why
A
- 13 polypeptides
- 2 rRNAS
-22 tRNAs
For oxidative phosphorylation
4
Q
What are key features of mtDNA(mitochondrial DNA)
A
- lacks introns
- Has mutation rate 10x higher than nucler DNA
-Susceptible to damage
5
Q
Why is the mitochondrial DNA susceptible to damage?
A
- Due to repair mechanisms
- Exposure to free radicals during oxidative phosphorylation
6
Q
What is heteroplasmy? (in relation to mitochondrial DNA)
A
- Where cells may contain a mix of normal and mutant mTDNA molecules
- The amount/porportion of mutant mtDNA detrmines the severity of mitochondrial diseases
7
Q
What type of organs are more severly affected by mtDNA molecules
A
- Organs with high ATP demands
8
Q
Name the types of mitochindrial mutations
A
- Misense mutations
- Single base mutations in tRNA genes
-Duplication and deletions
9
Q
What does misense mutations lead to
A
LHON
10
Q
What does LHON lead to
A
- Rapid loss of vision in the central field
11
Q
What does single base mutations lead to
A
- MERRF
- MELAS
12
Q
What does duplications and deletions lead to
A
-Kearns-sayre disease
- Pearson syndrome
- CPEO
13
Q
What does kearns-sayre disease lead to
A
- Muscle weakness and heart failure
