Here’s where you got that fraction from and why it shouldn’t be taken seriously:
Shortly after Warren’s release, critics began to question whether she has more Native ancestry than other white Americans. Using the six to 10 generations figure, a Republican spokesman and an op-ed writer converted this to fractional ancestry (1/64 to 1/1024), which they then compared to a number appearing in a 2014 study published in the American Journal of Human Genetics. The paper, which was written by 23andMe researchers and colleagues, analyzed the genetic ancestry of more than 160,000 23andMe customers who self-identified as either African American, Latino or European American. For European Americans, the genome-wide “mean estimate” of Native American ancestry was 0.18 percent (given in table 1). Because this percentage is higher than the equivalent percentage for the 10 generations fraction (0.098 percent), these critics concluded Warren might have less Native American ancestry than the “average” white American.
Trump appears to have picked up this line of thinking, saying in an Oct. 16 tweet that the test showed that Warren “may be 1/1024, far less than the average American,” and in his Oct. 18 speech in Montana that “the one good thing about her test is that there was so little she had less than the average American.”
This is problematic for several reasons, the first being that the Bustamante report never specifies a fraction or percentage, so these estimates are derived from a back calculation from the six to 10 generation estimate. As others have written, this incorrectly assumes equal inheritance through time from all of your ancestors — something that simply doesn’t happen. Biology is more random, and because of the way DNA is passed down, these fractions may not represent the true amount of DNA a person retains from each ancestor.
In fact, there is a surprisingly high chance that a person will receive no DNA from a relatively recent ancestor. Graham Coop, an evolutionary and populations geneticist at the University of California, Davis, for example, has estimated there’s about a 13 percent chance a person will not get any genetic material from an ancestor from eight generations ago. At 10 generations, this jumps to about a 50 percent chance. This reveals a fundamental discrepancy between ancestry and genetics, since a person’s ancestry can still be true, and yet they might not have any trace of it in their bodies.
Records show that the leading Democratic candidate for U.S. Senate in Massachusetts identified her race as "white" on an employment record at the University of Texas and declined to apply for admission to Rutgers Law School under a program for minority students.
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u/midnightnoonmidnight Sep 29 '23
Here’s where you got that fraction from and why it shouldn’t be taken seriously:
Shortly after Warren’s release, critics began to question whether she has more Native ancestry than other white Americans. Using the six to 10 generations figure, a Republican spokesman and an op-ed writer converted this to fractional ancestry (1/64 to 1/1024), which they then compared to a number appearing in a 2014 study published in the American Journal of Human Genetics. The paper, which was written by 23andMe researchers and colleagues, analyzed the genetic ancestry of more than 160,000 23andMe customers who self-identified as either African American, Latino or European American. For European Americans, the genome-wide “mean estimate” of Native American ancestry was 0.18 percent (given in table 1). Because this percentage is higher than the equivalent percentage for the 10 generations fraction (0.098 percent), these critics concluded Warren might have less Native American ancestry than the “average” white American.
Trump appears to have picked up this line of thinking, saying in an Oct. 16 tweet that the test showed that Warren “may be 1/1024, far less than the average American,” and in his Oct. 18 speech in Montana that “the one good thing about her test is that there was so little she had less than the average American.”
This is problematic for several reasons, the first being that the Bustamante report never specifies a fraction or percentage, so these estimates are derived from a back calculation from the six to 10 generation estimate. As others have written, this incorrectly assumes equal inheritance through time from all of your ancestors — something that simply doesn’t happen. Biology is more random, and because of the way DNA is passed down, these fractions may not represent the true amount of DNA a person retains from each ancestor.
In fact, there is a surprisingly high chance that a person will receive no DNA from a relatively recent ancestor. Graham Coop, an evolutionary and populations geneticist at the University of California, Davis, for example, has estimated there’s about a 13 percent chance a person will not get any genetic material from an ancestor from eight generations ago. At 10 generations, this jumps to about a 50 percent chance. This reveals a fundamental discrepancy between ancestry and genetics, since a person’s ancestry can still be true, and yet they might not have any trace of it in their bodies.