🚀 go-pugleaf

Professor Vonroach wrote:
> 
> On Wed, 03 Oct 2001 16:32:19 -0500, Steve <bozone@ripco.com> wrote:
> 
> > Mitochondrial DNA mutates at a steady rate
> >from environmental damage, and has been used to determine (we think) the
> >patterns of ancient human migration and genealogy.
> Junk science troll - using the necessary hot button word -
> environmental damage. No further communication is possible since you
> are a mental midget. By the way what do `we think' is damage and how
> is it differentiated from simple change.

I will, for the moment, ignore your ad hominem argument, O Dr. Science.

I refer to it as damage because mitochondrial DNA does not seem to
contain a mechanism for change other than mutation.  This is in contrast
to "standard" nuclear DNA which changes by way of sexual reproduction
and mutation.  I have not read any instance of a change in mtDNA
resulting in an advantage, but have read of some instances in which it
causes fatal or non-fatal metabolic defects.   If you want to call it
"change" I have no objection, as damage is simply a subset of change. 
The current estimate as to the rate of change is about one mutation
every 10,000 years.

There is some speculation that male mtDNA from sperm may somehow combine
with the otherwise exclusively matrilineal mtDNA (throwing a wrench into
the use of mtDNA to trace matrilineal ancestry and migration), but no
mechanism for this has as yet been proposed.  It has long been observed
that sperm mtDNA is destroyed upon fertilization, which further
confounds this line of speculation.