Genes & Genomes - Lec 4 - The human genome project - PART 2 Flashcards
When were neanderthals found?
150 years ago in Germany
Where did Neanderthals live?
Europe and west Asia
When did Neanderthals disappear?
30, 000 years ago
What is the big question in the comparative genetics of the nuclear genome between modern Humans and Neanderthals?
1) If modern humans and Neanderthals cohabited (interbreed)
2) If there was a geographical range in their time of existence
3) If Neanderthal groups adopted cultural traits that might have been influenced by modern humans
What happens to DNA following death?
Decays quickly: nucleases, microbial decomposition
How could DNA not decay after Death?
1) Rapid desiccation
2) Low Temperatures
3) Anaerobic conditions
4) High salinity
What happens to DNA with slow decay?
1) Depurination (loss of A and G bases)
2) Oxidative damage
3) Hydrolytic damage
4) Fragmentation
What was the first retrieval of old DNA?
1) Quagga DNA clones from museum specimen
2) 2430 year old Mummy DNA clones using bacterial cloning
How did PCR influence the Isolation of ancient DNA?
1) Get lots of DNA replication from little, sequence PCR products directly with no cloning
2) Permits targeted studies of specific genes or DNA regions.
How did NGS influence the Isolation of ancient DNA?
Ancient DNA is already fragmented, thus older, poorer preserved samples will already have smaller fragments
When and how much was the mammoth genome sequenced?
2008 - 70%
What was used for the sequencing of the mammoth
Hair preserved under ice, DNA was fragmented
What part of the Neanderthal body was used to study nuclear DNA?
Bone found in 1980 in a cave in Croatia, dating 38,310 -+ 2130 years
What is the challenge in terms of bone samples, for the Neanderthal species?
The bones are to degraded on contaminated with human sequences
Which sequencing two approached was used for the Neanderthal species?
1) 454 sequencing, uses small fragments of DNA, attach to beads and PCR every fragment to 10m copies. Photons are generated each time a base is incorporated (1 mil Bp)
2) Metagenomic approach, Inserting DNA fragments into plasmids and amplifying by bacteria. Sequence the inserts using either pyrosequencing on the sanger method. Can be used to target specific genes. (65, 000 Bp)
