>Dick Fischer wrote:
>>
>> Peter Ruest wrote:
>>
>> > Is there any _direct_ evidence for common ancestry between humans
> > > and apes?
> >
A particularly relevant paper is the following:
Johnson, W.E. and Coffin, J.M. Constructing primate phylogenies from
ancient retrovirus sequences. Proc. Natl. Acad. Sci. USA, 96:
10254-10260 1999
http://www.pnas.org/cgi/content/abstract/96/18/10254
Abs.
The genomes of modern humans are riddled with thousands of endogenous
retroviruses (HERVs), the proviral remnants of ancient viral
infections of the primate lineage. Most HERVs are nonfunctional,
selectively neutral loci. This fact, coupled with their sheer
abundance in primate genomes, makes HERVs ideal for exploitation as
phylogenetic markers. Endogenous retroviruses (ERVs) provide
phylogenetic information in two ways: (i) by comparison of integration
site polymorphism and (ii) by orthologous comparison of evolving,
proviral, nucleotide sequence. In this study, trees are constructed
with the noncoding long terminal repeats (LTRs) of several ERV loci.
Because the two LTRs of an ERV are identical at the time of
integration but evolve independently, each ERV locus can provide two
estimates of species phylogeny based on molecular evolution of the
same ancestral sequence. Moreover, tree topology is highly sensitive
to conversion events, allowing for easy detection of sequences
involved in recombination as well as correction for such events.
Although other animal species are rich in ERV sequences, the specific
use of HERVs in this study allows comparison of trees to a well
established phylogenetic standard, that of the Old World primates.
HERVs, and by extension the ERVs of other species, constitute a unique
and plentiful resource for studying the evolutionary history of the
Retroviridae and their animal hosts.
-- Preston Garrison, Ph.D. Instructor UTHSCSA Biochem. Dept. MSC 7760 Insert the usual disclaimers here. 7703 Floyd Curl Dr. San Antonio, TX 78229-3900 garrisonp@uthscsa.edu 210-567-3702 http://biochem.uthscsa.edu/~barnes
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