[sci.bio] Eve/Mitrochondrial DNA

rick@hanauma.Stanford.EDU (Richard Ottolini) (02/26/91)

There is also an "ADAM" study going on based on variation of the Y-chromosone
which is only passed on through the male side.  Nuclear genetic material is
more variable and difficult to work with than mitochondria genetic material,
so it might be some time before there are convincing results.

bryans@ux1.cso.uiuc.edu (B. Charles Siegfried) (02/26/91)

rick@hanauma.Stanford.EDU (Richard Ottolini) writes:


> Nuclear genetic material is more variable and difficult to work
> with than mitochondria genetic material,

	Wait a minute.  The mitochondria is the DNA that lacks a great
deal of proofreading ability, not the nuclear DNA.  I suppose there
are other difficulties since obviously the Eve study was completed
earlier than the Adam studies, but the malleability of the DNA certainly
isn't the reason.  Unless the Y chromosome is so unchangible that it
hasn't changed perceptibly in the last few hundred thousand years.

__
Bryan Siegfried                                            zig@uiuc.edu

ajpierce@ulah.med.unc.edu (Andrew Pierce) (02/26/91)

In article <1991Feb26.003300.6875@ux1.cso.uiuc.edu> bryans@ux1.cso.uiuc.edu (B. Charles Siegfried) writes:
>	Wait a minute.  The mitochondria is the DNA that lacks a great
>deal of proofreading ability, not the nuclear DNA.  I suppose there
>are other difficulties since obviously the Eve study was completed
>earlier than the Adam studies, but the malleability of the DNA certainly
>isn't the reason.  Unless the Y chromosome is so unchangible that it
>hasn't changed perceptibly in the last few hundred thousand years.

My understanding of this is that the difficulty here is that the
chromosomes are able to recombine with each other whereas with
mitochondrial DNA, there is nothing else there with which to recombine.
As far as tracing evolution goes, the mutation rate is not really as
important as having the mutations _random_ and the rate _constant_.  This
is not the case with genomic DNA where large rearrangements are possible.
     -Andy