<!--QuoteBegin-->QUOTE<!--QuoteEBegin-->From: "gktk_us" <tkgk9@...>
Date: Tue Feb 24, 2004Â 3:57 pm
Subject: [Y-Indology] Re: Genetic ResearchÂ
On a cursory look Dr. Bamshad's work does not look any different from
Dr Jorde's "Genetics evidence" which I had analysed earlier. Here it
is for those who are interested. I welcome any comments.
Regards,
======================================
--- In INDOLOGY@yahoogroups.com, "rkk" <rkk@N...> wrote:
> Geneticists should address a well-defined pilot project. Let them
> look at Parsis, Kashmiri Pandits, Namboodiri brahmins , and
> Ayyangars to see if there are commonalities..
> Rajesh Kochhar
http://www.uwm.edu/Dept/21st/projects/Gene...sity/jorde.html
I went through the above article. The article seems to be transcript
of Prof. Lynn Jorde's oral presentation. The slides are missing so
little can be said about it. (Lynn Jorde is Professor of Human
Genetics at the University of Utah. He has been involved in a
collaborative effort between geneticists, physical
anthropologists, and indigenous populations in India.)
It is my conclusion that the data presented by Prof. Jorde fits the
OIT better than the AIT/AMT. Here is my analysis of the article.
Early in the article Prof. Jorde presents the picture that he wants
to research (in Prof. Jorde's words):
"So here are some of the research questions that we've been
addressing in our studies in south India. First of all, is there
significant between-population genetic variation, and we've been
looking thus far primarily at caste variation, and what is the
pattern of between-caste genetic distances? What are the likely
origins of south Indian castes and tribal populations? And finally,
is there evidence of a sex-biased gene flow between castes? And this
is essentially the system that we were testing with mitochondrial and
Y-chromosome genetic markers, and I'll talk a little bit more about
that as we go along."
Later he builds his premise to test out the data he collected.
"Now, we can summarize -- and this is a very, very oversimplified
summary of major historical events in India, but it gives us at least
a framework from which to proceed -- Paleolithic settlement of
probable African origins, migrations of proto-Dravidian speakers from
the Fertile Crescent area about nine or ten thousand years ago. And
then most recently, a third major event, migrations of Indo-European-
speaking, so-called Aryans from West Asia, about 3500 years ago, and
it was these individuals who established, who are thought
to have established, the caste system. And I'll be referring to these
waves of migration as we go through the talk."
It is clear that the premise of Prof. Jorde's research is based on
the AIT/AMT.
So, strictly speaking, this presentation cannot be taken as a proof of
migration. This presentation can be limited to what Prof. Jorde set
out to prove namely: Genetic variation and caste. However, lets see
how it all goes.
Prof. Jorde first shows that genetic variations across the caste
exists. A loose summary goes like this: The transmission of
mitochondrial DNA across generations is associated with the female of
the species while Y-chromosomal DNA is associated with the male. It
is observed that females had greater mobility across the castes as
opposed to males. The more homogenous nature of the motochondrial DNA
across the castes shows this, while a 6-7 times higher
variation in Y-chromosomal DNA in males of the population shows their
lower mobility across the castes.
For the "cricitcal" conclusions, which "prove" AIT/AMT, I'll use
Prof. Jorde's words:
"Now, we can also look at -- and this is some fairly new work that
hasn't yet been published -- mitochondrial DNA, genetic distances
between various caste groups and continental populations. And one of
the things we see here is that all of the castes are most similar to
groups of Asian populations. And that's expected, given the origins
of the proto-Dravidian populations, so that we see much, much smaller
distances between Asian populations and each of the caste
groups for the mitochondrial DNA."
Comments: Given the geographical isolation of the sub-continental
population for long periods of time and the female mobility across
castes, a homogeneity in mitochondrial DNA is not totally unexpected,
even according to Prof. Jorde's analysis. IOW, assumption of the
existence of a proto-Dravidian population is unnecessary.
Further Prof. Jorde says:
"When we look at Y chromosome DNA, we again see a somewhat different
pattern. For the upper castes, they actually have slightly greater
genetic affinity (smaller distances) for European populations than
for any other population. The middle castes, a little bit smaller
distance between them and Europeans, and the lower castes instead
have the greatest affinity to Asian populations."
Comments: ".....greatest affinity to Asian populations"? This is
ambigous. If it refers to the Dravidian population as Prof Jorde
previously alluded, then it is fictitious comparision since, then he
is comparing the supposed "lower caste" with themselves and obviously
a good match will be found.
OTOH, it would be naive to imagine that the population across whole
of Europe has very low variation in Y-chormosomal DNA. It would be
interesting to see which European population set has the maximum
affinity to the "upper caste".
And then he concludes;
"Now, if we think back about the history of the population, the most
recent wave, and the one that is the most recent wave of migrants,
the one that instituted the caste system is thought to have come from
West Asia, Eurasia, and those individuals would likely have been more
similar to individuals from Europe. And as those individuals who
began the caste system, they also likely appropriated the highest
positions in the system. So, a very interesting historical insight,
again consistent with some historical hypotheses that the
invaders who came in about 3500 years ago, established the system, and
primarily who were male, so we see the Y chromosome versus
mitochondrial difference, we can still see that signature in today's
genes."
Comments: Prof. Jorde started with a premise and his data set proves
it. If Prof. Jorde had started with a different premise, will the
data-set disprove the different and incorrect premise? Theoretically,
it should. Let see how the data set fits for example the OIT. We take
OIT because, it runs diametrically opposite to AIT/AMT.
But, first, let us re-build the premise.
<b>
In 3500 BP or so the life-sustaining ability of river Saraswathi was
on decline. Migrations of population from its banks began. It is well
known that the "upper caste" brahmin population migrated down the
coast upto Kerala, populating the regions all along the way. The
saraswath brahmins the tulu-brahmins the namboodris are examples and
there is hardly any dispute in this. The other wave moved across to
the gangetic plains and upto Brahmaputra.</b>
I am afraid I have little to go on here. (Can somebody tell me more?)
But what about the other castes? Did they move along with them? What
artefacts have they left behind I have no idea. <b>However, it is
tempting to assume that the "upper class" mobility was much higher.
As it turns out, this is the ONLY assumption one has to make to fit
Prof Jorde's data-set to OIT! Lets see how.</b>
Now, it is downright silly to assume that R. Saraswathi was populated
only on the Eastern bank! What happened to those who lived on the
west side? Did they die out as the Saraswathi dried up? Likely no.
They too migrated? Very possible. Where did they migrate to? Did they
run across the river and into the eastern side? Possible too. But,
did they moved out to present-day Afghanistan and beyond, through to
Middle-East and to Europe!! Lets pick up this possibility and see how
Prof Jorde's data fits.
No disputes about the variation of the Y-chromosomal DNA and
similarities of the mitochondrial DNA across the castes in the sub-
continent. The issue is the similarity of the Y-Chromosomal DNA of
the European population with that of the "upper caste" with gradually
decreasing similarities with other castes. This can easily be
explained as a representation of the mobility pattern. The "upper
caste" had a higher mobility and moved to Europe. The homogenization
of the Y-Chromosome can be explained as the lack of "caste-system"
and it is no surprise that this homogenized population's Y-Chromosome
DNA shows greater similarity to the population that showed the
greatest mobility - namely - the "upper caste".
So, as compared to Prof. Jorde's premise, where he had to make several
assumptions (the Aryan invasion into India, mostly male, formation of
caste system by them, appropriation of the "higher caste" by these
invaders etc.), one has to use just one simple and probably very
likely assumption that the so called "upper caste" had higher
mobility and the premise of "OIT" fits much better.
Guess, the idea is, the lesser the assumptions one has to make to fit
a data-set, the higher the probabilty of the theory to be true.
<!--QuoteEnd--><!--QuoteEEnd-->
Date: Tue Feb 24, 2004Â 3:57 pm
Subject: [Y-Indology] Re: Genetic ResearchÂ
On a cursory look Dr. Bamshad's work does not look any different from
Dr Jorde's "Genetics evidence" which I had analysed earlier. Here it
is for those who are interested. I welcome any comments.
Regards,
======================================
--- In INDOLOGY@yahoogroups.com, "rkk" <rkk@N...> wrote:
> Geneticists should address a well-defined pilot project. Let them
> look at Parsis, Kashmiri Pandits, Namboodiri brahmins , and
> Ayyangars to see if there are commonalities..
> Rajesh Kochhar
http://www.uwm.edu/Dept/21st/projects/Gene...sity/jorde.html
I went through the above article. The article seems to be transcript
of Prof. Lynn Jorde's oral presentation. The slides are missing so
little can be said about it. (Lynn Jorde is Professor of Human
Genetics at the University of Utah. He has been involved in a
collaborative effort between geneticists, physical
anthropologists, and indigenous populations in India.)
It is my conclusion that the data presented by Prof. Jorde fits the
OIT better than the AIT/AMT. Here is my analysis of the article.
Early in the article Prof. Jorde presents the picture that he wants
to research (in Prof. Jorde's words):
"So here are some of the research questions that we've been
addressing in our studies in south India. First of all, is there
significant between-population genetic variation, and we've been
looking thus far primarily at caste variation, and what is the
pattern of between-caste genetic distances? What are the likely
origins of south Indian castes and tribal populations? And finally,
is there evidence of a sex-biased gene flow between castes? And this
is essentially the system that we were testing with mitochondrial and
Y-chromosome genetic markers, and I'll talk a little bit more about
that as we go along."
Later he builds his premise to test out the data he collected.
"Now, we can summarize -- and this is a very, very oversimplified
summary of major historical events in India, but it gives us at least
a framework from which to proceed -- Paleolithic settlement of
probable African origins, migrations of proto-Dravidian speakers from
the Fertile Crescent area about nine or ten thousand years ago. And
then most recently, a third major event, migrations of Indo-European-
speaking, so-called Aryans from West Asia, about 3500 years ago, and
it was these individuals who established, who are thought
to have established, the caste system. And I'll be referring to these
waves of migration as we go through the talk."
It is clear that the premise of Prof. Jorde's research is based on
the AIT/AMT.
So, strictly speaking, this presentation cannot be taken as a proof of
migration. This presentation can be limited to what Prof. Jorde set
out to prove namely: Genetic variation and caste. However, lets see
how it all goes.
Prof. Jorde first shows that genetic variations across the caste
exists. A loose summary goes like this: The transmission of
mitochondrial DNA across generations is associated with the female of
the species while Y-chromosomal DNA is associated with the male. It
is observed that females had greater mobility across the castes as
opposed to males. The more homogenous nature of the motochondrial DNA
across the castes shows this, while a 6-7 times higher
variation in Y-chromosomal DNA in males of the population shows their
lower mobility across the castes.
For the "cricitcal" conclusions, which "prove" AIT/AMT, I'll use
Prof. Jorde's words:
"Now, we can also look at -- and this is some fairly new work that
hasn't yet been published -- mitochondrial DNA, genetic distances
between various caste groups and continental populations. And one of
the things we see here is that all of the castes are most similar to
groups of Asian populations. And that's expected, given the origins
of the proto-Dravidian populations, so that we see much, much smaller
distances between Asian populations and each of the caste
groups for the mitochondrial DNA."
Comments: Given the geographical isolation of the sub-continental
population for long periods of time and the female mobility across
castes, a homogeneity in mitochondrial DNA is not totally unexpected,
even according to Prof. Jorde's analysis. IOW, assumption of the
existence of a proto-Dravidian population is unnecessary.
Further Prof. Jorde says:
"When we look at Y chromosome DNA, we again see a somewhat different
pattern. For the upper castes, they actually have slightly greater
genetic affinity (smaller distances) for European populations than
for any other population. The middle castes, a little bit smaller
distance between them and Europeans, and the lower castes instead
have the greatest affinity to Asian populations."
Comments: ".....greatest affinity to Asian populations"? This is
ambigous. If it refers to the Dravidian population as Prof Jorde
previously alluded, then it is fictitious comparision since, then he
is comparing the supposed "lower caste" with themselves and obviously
a good match will be found.
OTOH, it would be naive to imagine that the population across whole
of Europe has very low variation in Y-chormosomal DNA. It would be
interesting to see which European population set has the maximum
affinity to the "upper caste".
And then he concludes;
"Now, if we think back about the history of the population, the most
recent wave, and the one that is the most recent wave of migrants,
the one that instituted the caste system is thought to have come from
West Asia, Eurasia, and those individuals would likely have been more
similar to individuals from Europe. And as those individuals who
began the caste system, they also likely appropriated the highest
positions in the system. So, a very interesting historical insight,
again consistent with some historical hypotheses that the
invaders who came in about 3500 years ago, established the system, and
primarily who were male, so we see the Y chromosome versus
mitochondrial difference, we can still see that signature in today's
genes."
Comments: Prof. Jorde started with a premise and his data set proves
it. If Prof. Jorde had started with a different premise, will the
data-set disprove the different and incorrect premise? Theoretically,
it should. Let see how the data set fits for example the OIT. We take
OIT because, it runs diametrically opposite to AIT/AMT.
But, first, let us re-build the premise.
<b>
In 3500 BP or so the life-sustaining ability of river Saraswathi was
on decline. Migrations of population from its banks began. It is well
known that the "upper caste" brahmin population migrated down the
coast upto Kerala, populating the regions all along the way. The
saraswath brahmins the tulu-brahmins the namboodris are examples and
there is hardly any dispute in this. The other wave moved across to
the gangetic plains and upto Brahmaputra.</b>
I am afraid I have little to go on here. (Can somebody tell me more?)
But what about the other castes? Did they move along with them? What
artefacts have they left behind I have no idea. <b>However, it is
tempting to assume that the "upper class" mobility was much higher.
As it turns out, this is the ONLY assumption one has to make to fit
Prof Jorde's data-set to OIT! Lets see how.</b>
Now, it is downright silly to assume that R. Saraswathi was populated
only on the Eastern bank! What happened to those who lived on the
west side? Did they die out as the Saraswathi dried up? Likely no.
They too migrated? Very possible. Where did they migrate to? Did they
run across the river and into the eastern side? Possible too. But,
did they moved out to present-day Afghanistan and beyond, through to
Middle-East and to Europe!! Lets pick up this possibility and see how
Prof Jorde's data fits.
No disputes about the variation of the Y-chromosomal DNA and
similarities of the mitochondrial DNA across the castes in the sub-
continent. The issue is the similarity of the Y-Chromosomal DNA of
the European population with that of the "upper caste" with gradually
decreasing similarities with other castes. This can easily be
explained as a representation of the mobility pattern. The "upper
caste" had a higher mobility and moved to Europe. The homogenization
of the Y-Chromosome can be explained as the lack of "caste-system"
and it is no surprise that this homogenized population's Y-Chromosome
DNA shows greater similarity to the population that showed the
greatest mobility - namely - the "upper caste".
So, as compared to Prof. Jorde's premise, where he had to make several
assumptions (the Aryan invasion into India, mostly male, formation of
caste system by them, appropriation of the "higher caste" by these
invaders etc.), one has to use just one simple and probably very
likely assumption that the so called "upper caste" had higher
mobility and the premise of "OIT" fits much better.
Guess, the idea is, the lesser the assumptions one has to make to fit
a data-set, the higher the probabilty of the theory to be true.
<!--QuoteEnd--><!--QuoteEEnd-->