Genetic studies of early human populations Flashcards
when was H. erectus in africa vs when in Eu/asia
- 9mya
1. 8mya
when was H. neaderthalensis in Eu
200-30kya
when did Homo sapiens in Afr
195kya
when did homo sapiens in eu
65kya
how do genetic studies study human pre history
look at modern pops to make sense of ancient
how is genetic diversity found in modern pops and how has this changed
dna seq
used to be only mt DNA and y chr dna
now whole genome
what are some methods for infering deviersity evolution
phylogenetics - patterns of div as tree/network
dating - method assign dates to key positions in an ev scheme
phylogeographic - interpret diversity of pop migr
what are the problems with the methods for infering the diversity evolutio
do they produce anything real or just a narrative
lots of diff way data can be interpreted
lots of data - lot of computer power required
why is mtdna good to study
most rapidly ev part of genome
easy seq
what is the d loop
the most variable part of mt dna
lot of ev here as no sel pressure as there are no genes on this bit of dna as it is the origin of replication
most early studies used dloop amplified by pcr
what has next gen seq meant for mt dna studies
now look at whole genome of mt dna not just d loop
put into haplogroups
what arehaplogroups
275
diff groups assoc with diff parts of the world
not distinct seq but related seq
have subsitututions which categorise
what are haplogroups made up of
haplotypes - mixture of seq
share subsitiutions of haplogroup
but have own distinct substitutions that define (these allow the ev relationships between haplotypes to be worked out)
if haplotypes are rare this shows
the result of recent mut
how are networks built
compare subsitutions
want maximum parsimony
trees are diff ypothesis that make sense of the data
networks - lots of diff trees
