Genome shaping mechanisms Flashcards
1
Q
What are 5 mechanisms to explain why our genome looks the way it does?
A
- Whole genome duplication
- Replicative transposition
- Unequal crossing over
- Strand slippage
- Segmental duplications
2
Q
How do whole genome duplications happen?
A
Failure of the mitotic spindle to segregate the chromosomes
3
Q
What is the result of whole genome duplication?
A
Autoploidy. Triploid and tetraploid individuals
4
Q
Why does replicative transposition shape our genome?
A
Every time a LINE element moves, it goes by copy and paste and adds an extra 6 kb of DNA
5
Q
Why does unequal crossing over shape our genome?
A
Generates deletions and duplications
6
Q
Why does strand slippage shape our genome?
A
Repetitive sequences contract or expand
7
Q
What are segmental duplications?
A
When part of one chromosome gets duplicated and the same sequences are found on two chromosomes in the same orientation
