Lecture 23: what does the genome tell us about being human Flashcards
how do you compare sequences
by aligning
what is alining
lining sequences up next to each other and marking each point where sequences are the same
by comparing genomes between individuals we can find out…
where differences occur
differences of genomes might be associated with:
- disease
- characteristics of an individual
- evolutionary history
cost of sequencing human genome
$4000 USD
what could we learn about an organism if we compare its genome with others:
- what sort of genes they have
- how differences between species arise
- relationships between species
DNA from dead things…
can remain in the environment
DNA degrades and is masked…
by more modern DNA
DNA bases are also modified as they degrade…
sometimes changing in sequence
ancient DNA can be extracted…
and identified in very special circumstances
ancient DNA has been used to determine…
the relationship of extinct animals, like Mao and mammoths
genomics in common are called
“conserved”
conserved genomics
may encode the same biology between two species
different genomics
may encode organism specific biology
closest relatives to modern humans
Neanderthals
amount on neanderthal nucleotides
4 billion
some humans carry…
Neanderthal DNA
modern humans from Europe and Asia carry…
Neanderthal alleles
individuals from Africa…
show no sign of Neanderthal alleles
when modern humans met neanderthals…
they interbred
homosapiens and neanderthals have
a common ancestor
some humans carry…
neanderthal DNA
humans with neanderthal DNA holds variants…
that arose in neanderthals
2-4% of the genome of non africans is made…
of variants that arose in neanderthals
Neanderthal DNA adds variation to our genome that might…
be related to our phenotype
Denisovan variation is found
in modern human genome
Denisovans variation makes up
4-6% of genomes of present day Melanesians
having sequenced genomes we can…
compare them
