I have just finished reading Java Man by Swisher, Curtiss and Lewin. In
there they referenced an article by Ruvolo which was a statistical analysis
of genetic studies which purport to show that the out-of-Africa hypothesis
is correct. I was amazed to find the following in this article, in which the
standard 'European' mtDNA sequence is partly cow. Being of European descent
this explains why every now and then I get the urge to eat grass!
“One aspect of these data should be viewed as tentative. As Horai et al
(1995) observe, their estimate of 70,000 years for the inferred divergence
date between European and Japanese mtDNA is older than that calculated from
gene frequency data (55,000). Because of suspected inaccuracies with the
standard human reference sequence, Horai et al (1995) used an edited version
of it, changing bases at seven sites, based on data from other humans and
hominoids. However, the original representative ‘European’ mtDNA sequence
comes from more than one individual; most is presumably of European origin
but some of the sequence (unspecified amounts at unspecified positions) was
derived from HeLa cells. Since this cell line was established from Henrietta
Lacks, an African-American woman, some of the ‘European’ reference sequence
(even the slightly edited version) is likely to be closer to the African
sequence in certain mitochondrial regions. If on average Africans are
mitochondrially more distant from other populations, this could potentially
make the measured ‘European’ Japanese genetic difference greater and and
give an artificially older date for their divergence. This is indeed what
the data show: the ‘European’-African difference is slightly less than the
Japanese-African difference: 93 versus 106 bp different, respectively. Also,
the ‘European’ reference sequence is not exclusively human: five bp at known
sites could not be determined unambiguously and were therefore taken to
match that of the cow. Use of this mosaic ‘European human’ reference
sequence potentially affects inferences about divergences between Europeans
and other human populations. Its use should have only a negligible effect on
the inferred divergence date for modern humans, given what is known about
the degree of genetic difference of true European mitochondrial sequences
from those of other populations. Nevertheless. It highlights the need to
sequence at least one complete mitochondrial genome from a single European,
to use in place of the standard reference sequence. This same ‘European’
reference sequence has been used in several other mtDNA studies (Cann et
al., 1987; Vigilante et al., 1989, 1991; Kocher and Wilson 1991; Ruvolo et
al 1993)” MaryEllen Ruvolo, “A New Approach to Studying Modern Human
Origins: Hypothesis Testing with Coalescence Time Distributions,” Molecular
Phylogenetics and Evolution 5(1996):1, p. 202-219, p. 209
One might think that replacement theory researchers would cease using this
sequence given the mosaic nature of it. But such is not the case. Consider
the comparison of mtDNA from a Neanderthal in which the Anderson sequence
was used as the primary European comparative mtDNA! Consider this from
Ovchinnikov et al "Molecular analysis of Neanderthal DNA from the northern
Caucasus" Nature 404, 490 - 493 (2000)
"Comparison of the 345-bp fragment of HVRI with the Anderson reference
sequence 11 and the Neanderthal from Feldhofer Cave 4 revealed 22
differences (17 transitions, 4 transversions and 1 insertion) and 12
differences (11 transitions and 1 transversion), respectively. The Feldhofer
Neanderthal HVRI contained 27 differences to Anderson reference sequence 11
(over the equivalent 345 bp"
The reference to the Feldhofer Cave specimen is to the original mtDNA study
of Neanderthals. Because of the inclusion of bovine mtDNA base pairs into
the standard "European" sequence it certainly calls to question the
conclusion that Neanderthal mtDNA is too far from modern human mtDNA for
them to be -- human.
glenn
see http://www.glenn.morton.btinternet.co.uk/dmd.htm
for lots of creation/evolution information
anthropology/geology/paleontology/theology\
personal stories of struggle
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