What do you mean by "indigenous" descent in elizabeth warren?

On March 3rd, 2065438, Senator elizabeth warren gave a speech in * * *. (Scott Eisen/Getty photo) On Monday, Senator D-Mass. Announced the results of the DNA test, indicating that she has Native American ancestry, and put the genetic test and Native American identity in the spotlight.

The DNA report was released after years of political exchanges between Warren and his party opponents, who accused Warren of pretending to be a Native American to advance her legal career. The DNA "fact check" of a political debate, even before a few election cycles, will be like science fiction. However, even today, DNA ancestor testing is not as simple as it seems, especially in finding Native American identity. [How is the [DNA ancestor test conducted? Matthew anderson, a geneticist at Ohio State University, said:

"It is important to think about the origin of community and culture."

Warren was born and raised in Oklahoma. She always thought that her mother's relatives were of Native American descent. This is a family story handed down from generation to generation. New DNA tests show that there are indeed five fragments in Warren's genome belonging to Native Americans. Carlos Bustamante, a geneticist at Stanford University who conducted this analysis, told The Boston Globe that Warren had Native American ancestors before 6 to 10 generations. According to geneticists contacted by Life Science, the results seem credible. J.Douglas McDonald, emeritus professor of chemistry at the University of Illinois, said:

Bustamante's evaluation is "good enough to do as he says", and he developed biogeographic analysis software for ancestor testing.

But Warren's grades are not enough to make her a member of the tribe. The tribe decides its own roster (member list) and does not use DNA ancestor test. Some people use genealogy research to set certain requirements for the proportion of Native American descent required for membership. Others require applicants to prove that they are related to people who are already on the list of tribal members.

"DNA testing is useless for determining tribal citizenship," Cherokee Secretary of State Chuck Hosking Jr. said in a statement. Today's DNA testing can't even tell whether a person's ancestors were Native Americans or South Americans.

In fact, Bustamante told the Boston Globe that he compared Warren's gene sequence with the gene fragments of indigenous groups in South America, because only limited data can be obtained from indigenous groups in North America. Because the aborigines in South America and North America have the same ancestor-this group may have crossed the Bering Strait at least 15000 years ago-they also have more homologous gene sequences than people of European descent. But the information is too vague to classify a person's ancestors into a tribe. [in the photo: human bones provided clues for the first Americans]

Complex genes In fact, no DNA test can conclusively prove or refute that a person has an ancestor of a particular race. Anderson said that these results are reported in probability rather than certainty. This is because of the way genes are transmitted.

When you cross your family tree, the proportion of DNA contributed by each relative in your genome becomes smaller and smaller. Your parents each contribute about 50%; When you find 16 great-great grandparents, each of them only contributed 6.25% DNA to you. Your 64 great-great grandparents each contributed only 1.56%.

It is easy to imagine that if only one of the 64 great-great grandparents is native American, and their contribution rate is in your other DNA, this kind of pollution is difficult to find, especially because commercial DNA testing has not screened out the whole genome, but only screened out some fragments. (According to geneticist T.L. Dixon (Roots &; Recomination DNA), different commercial tests will also screen different genomic fragments, which is why the ancestral results of each test may be slightly different. )

This picture becomes more blurred because the amount of DNA passed down is not fixed. When DNA strands are handed down from * * * and eggs, they will be randomly recombined; This random reorganization may mean that the contribution rate of any great-great grandparents is even lower than the theoretical allocation of 1.56%. Anderson said, "Digital Genetics: 10 fascinating stories".

"Your DNA is half inherited from your mother and half from your biological father." Obviously, but where did your parents' DNA come from? That's a mixture of their parents. It may really be biased towards grandparents 1 instead of grandparents 2. Because of this recombination, the genetic contribution of a known ancestor can basically disappear or be washed away after several generations. When a specific population is blocked, the elution of "kdspe" and "kdsps" genes becomes particularly possible. Dixon wrote that because of the policy adopted by the United States, indigenous people were driven away from their land and isolated on reservations, and the wider population, as happened to native Americans. This means that someone may have an ancestor of Native Americans, but there is no genetic contribution from that ancestor in their DNA.

On the other hand, KDSP tests reveal the same fragments of Native Americans, but they can't prove that your ancestors were indigenous. Because Native Americans and East Asians have the same ancestor, the gene fragment of "Native Americans" may have originated from East Asian ancestors. Qiao Lin said, again, it's all about probability. Generally speaking, the more fragments you are associated with a certain race, the more likely you are to be a descendant of that race. However, because these mutations appear in different populations and frequencies around the world, Anderson said, "Just because you have a specific mutation, you are born from a specific population, which is challenging." The historical policy about who is an Indian also blurs the boundaries. 1700 and 1800, some Asians immigrated to the United States. Among Native Americans, due to the mixing of different populations in European history, many tribal members are now full of DNA from Europe, Africa and Asia. This may mean that people who are legally and culturally native Americans have relatively few DNA sequences.

An example of ancestry and cultural complexity is the Cherokee Freeman case, which was disputed by the Cherokee National Supreme Court on the issue of tribal membership in 2006. Cherokee freemen are descendants of Cherokee tribesmen. After liberation, these freemen were allowed to join Cherokee for the first time. However, in the 1980s, the citizenship law of the tribe changed, requiring a kinship with a tribe member on the federal Cherokee member list in the early 20th century. This change deprived many free people of their tribal citizenship, even though they were Cherokee culturally and descended from Cherokee relatives. The legal debate continued until 20 17, when the U.S. district court ruled that freemen had the right to Cherokee citizenship, and the Cherokee people accepted the ruling.

"People forget that the black people we assume can also be Native Americans, and they are completely excluded from these conversations," Anderson said.

According to the American Indian and Alaska Native Genetic Resource Center (American Indian & Alaska Native geics Resource Center), due to the history of forced migration and assimilation of tribes, they are very cautious about genetic testing. The interaction between tribes and medical researchers is also worrying, just like the project between Arizona State University and the Grand Canyon Ha Vasu tribe. In this case, blood samples originally collected in the late 1980s were later used in other research projects without the consent of the participants, which led to litigation. Some tribes, such as the Navajo, have issued a ban on genetic research on their land. Other tribes, such as the Pima-Maricopa Indian community in Yanhe River, have established cooperative relations with researchers, so they have a say in how to conduct research. Nevertheless, according to Dixon, compared with some other races, the DNA data of Native Americans are still relatively scarce.

Anderson said that the emergence of commercial genetic testing has crowded the offices of many tribal organizations with applications based solely on DNA results. MacDonald said that although many early tests overestimated the possibility of being based on a small number of ancestors, today's ancestor tests seem to do better in avoiding false results. However, no matter how accurate these tests are, they cannot determine the identity of Native Americans.

"What part of the community you are, what stories you have and what traditions you keep," he said, these things determine who you are, not which part of the genome you have.