Across the country there
is currently a lot of interest in the prospects of using
genetics to determine whether somebody is really Native
American. This interest has arisen in many contexts,
from determining whether ancient remains are Native
American for purposes of repatriation, to groups of
people who are seeking recognition as an Indian tribe
by the United States government, to individuals who
think they might have American Indian ancestry and would
like to find a way to prove it. There are
even several companies that claim to be able to help
people determine their Native American heritage with
genetic analysis. In the notorious case of Kennewick
Man, (a 9,200 year old skeleton found in Kennewick,
WA, and claimed by both scientists and Native Americans)
geneticists were charged with the impossible task of
identifying him racially and tribally, and were of course
unsuccessful in spite of having destroyed some of the
remains to do the tests.
There are numerous problems with using genetics to determine
whether or not one has Native American ancestry, and/or
alternatively to determine tribal membership. The most
obvious problem is that being Native American is a question
of politics and culture, not biology: one is Native
American if one is recognized by a tribe as being a
member. And one is not necessarily a member of a tribe
simply because one has Native American ancestors. Another
problem is that genetic analysis, and some of the processes
involved, can be problematic for indigenous people in
terms of their own cultural knowledge. Put simply, there
are things involved in genetic analysis that some indigenous
cultures consider violations of their principles or
values.
The point that is frequently
lost in the debate about using genetic analysis to determine
whether one is Native American is that the genetic analysis
itself is not conclusive, even on strictly scientific
terms. This article will explain the scientific shortcomings
of trying to use genetic analysis to prove native identity.
It is limited to the scientific shortcomings, but the
real legal, political, social, and moral issues should
also not be ignored.
The Theory: Native American
Genetic Markers
To begin, an explanation
of the theory behind using genetics to determine Native
American identity is in order. Scientists have found
certain variations, or markers in human
genes that they call Native American markers because
they believe all original Native Americans
had these genetic traits. The theory is that, if a person
has one of these markers, certain ancestors of the person
must have been Native American.
The markers are principally analyzed in two locations
in peoples genetic material: in their mitochondrial
DNA (mtDNA) and on the Y-chromosome. On the mitochondrial
DNA, there are a total of five different haplotypes(DEFINE),
called A, B, C, D, and X, which are increasingly called
Native American markers, and are believed
to be a genetic signature of the founding ancestors.
As for the Y-chromosome, there are two primary lineages
or haplogroups (DEFINE) that are seen in
modern Native American groups, called M3 and M45. Some
scientists maintain that up to 95% of all Native American
Y-chromosomes are from these two groups (the rest being
from either Asian lineages or non-native haplogroups).
It must be emphasized that none of these markers is
exclusive to Native American populations; all can be
found in other populations around the world. They simply
occur with higher frequency in Native American populations.
Y-chromosome and mtDNA markers are the most commonly
used genetic markers for the analysis of Native American
ancestry. But how does testing for these genes work?
Mitochondrial Analysis for Native American Marker Genes
Both females and males inherit their mtDNA only from
their mother. This line of biological inheritance, therefore,
stops with each male. That means that, if you think
of your 4 great-grandmothers, you and all your brothers
and sisters have inherited your mtDNA only from your
maternal grandmothers mother. Your other 3 great-grandmothers
and your 4 great-grandfathers have contributed none
of your mtDNA. If you are female, you and your sisters
will, in turn, transmit that great-grandmothers
mtDNA to all your children, but your brothers wont
transmit it to their children. In other words, your
mtDNA is identical to that of your mothers mothers
mother, but does not constitute a biological line of
descent from your other 7 great-grandparents. If that
great-grandmother happened to have the genetic variations
that have been labeled A, B, C, D, or X, then, by having
the same mtDNA yourself, you will have inherited a Native
American mtDNA marker.
Of course, if all your other great grandparents were
Native American, and your mothers mothers
mother was non-Indian, then you will most likely not
have one of the Native American mtDNA haplotypes.
So, 7 of your 8 great-grandparents may be Indian, and
yet you would not be identified as Indian by this test.
Moreover, it really goes farther than that, since the
mtDNA only comes from the purely maternal line. If you
go back two more generations, 31 of your 32 great-great-great
grandparents could be Indian. Yet you could not be identified
as Native American using this test if that one of your
16 (great-great-great) grandmothers who is part of your
female lineage was not Native American (or more specifically
if her mother did not have one of the five haplotypes
called Native American.) Keep going back
further, and still only a single one of your female
ancestors is detectable, while the number of ancestors
invisible to this test increases enormously.
Y-Chromosome Analysis
for Native American Markers
Males inherit a close copy
of their Y-chromosome from their fathers. Generally,
females do not have a Y-chromosome. So in addition to
the mtDNA tests, males can also be tested for Native
American markers on their Y-chromosome, but the
analysis has similar limitations as testing mtDNA. Here
again, the test only traces one line of ancestry, and
misses most of the subjects ancestry because the
vast majority of the ancestors are invisible to the
test. If a man has 15 Native American great-great-grandparents,
but his fathers fathers fathers father
was non-Indian, that person will not appear to be Native
American by this test. So, almost 94% of that persons
genetic inheritance may be from Native Americans, but
under this test he may be identified as non-Indian.
And, like mtDNA analysis using the purely maternal line,
using Y-chromosome analysis to determine Native American
ancestry ignores a greatly increasing percentage of
a persons ancestry as you go further into the
past with the analysis.
The Tests Yield False
Negatives
These discussions of mitochondrial
and Y-chromosome testing for Native American ancestry
have already indicated that it is very easy to get a
false negative using these teststhere is
a very high chance of someone having a significant amount
of Native American ancestory, and yet appearing to be
non-Native. All it takes is one non-Native person located
in the proper position in a persons ancestry.
There is another possibility of false negatives from
these types of tests as well. This other type of false
negative would arise if some Native American people
simply do not have one or more of the Native American
markers. Scientists have not tested all Native Americans,
so they do not know for sure that Native Americans only
have the markers they have identified, even when their
maternal or paternal bloodline does not include a non-Indian.
Real peoples are not bound by the geneticists
ideal of purity. The scientists already admit to some
of this uncertainty when they estimate that, for example,
95% of Native American men without a known non-Native
in their purely paternal line (fathers fathers
father, and so on) have one of the two Native
American variations they have identified. This
implies that at least 5% of the men can have other genetic
markers.
The Tests Also Yield
False Positives
Some of the haplotypes attributed
to Native Americans are also found in people from other
parts of the world. A, B, C, and D are found in North
Asia, and X is found in southern Europe and Turkey.
In fact, haplotype B, also called the Asian 9
base pair deletion, is found in some Japanese
and almost all Samoans. Can a person who has haplotype
B in her mtDNA claim to be Native American based on
that information if almost all Samoans also have haplotype
B? These tests cannot even establish with certainty
that someones mothers mothers mother
was Native American; they can at best establish a certain
probability that this was the case.
Tribes Do Not Differ
From One Another In Ways That Geneticists Can Detect
Another issue is the widespread
belief that genetics can help determine specific tribal
affinities of either living or ancient people. This
is quite simply false. Neighboring tribes have long-standing,
complex relationships involving intermarriage, raiding,
adoption, splitting, and joining. These social-historical
forces insure that there cannot be any clear-cut genetic
variants differentiating all the members of one tribe
from those of nearby tribes. At most, slight differences
in the proportions of certain genetic variations are
identifiable in each group, but those do not permit
specific individuals to be assigned to particular groups.
CONCLUSION
The concept of using genetic
tests to prove Native American ancestry is of relatively
recent origin, but there are many problems with it.
Perhaps foremost of these problems is that to make a
genetic test the arbiter of whether someone is Native
American is to give up a tribes sovereign ability
to determine its own membership and relations. But,
even taken on their own scientific terms, these tests
cannot do much to identify who is and who is not Native
American, because they yield many false negatives and
false positives. Therefore, they readily misidentify
non-Native people as Native, and misidentifying Native
people as non-Native, and the positive results they
do yield are at best only probabilities. If these were
medical diagnostic tests, they would never be approved
or adopted.
But the most important argument against this type of
testing to establish tribal affiliations is that biology
(and genetics) track just part of our tribal inheritance.
These DNA tests treat Native American biology
as though all Indians were essentially the same. But
in reality, it is our traditions that make us who we
are, not just our biology.
This is a briefing paper
published by the Indigenous People Council on
Biocolonialism, P.O. Box 818, Wadsworth, Nevada 89424.
Ph: (775) 835-6932. Fax: (775) 835-6934.
E-mail: ipcb@ipcb.org.
Web: www.ipcb.org
Brett Lee Shelton, J.D., is Director of Policy and Research
for IPCB.
Jonathan Marks, Ph.D., is Professor of Anthropology
at the University of North Carolina and a member of
IPCB's Board of Directors.