But ancestors do not contribute genetic material equally over time. Here’s the image of 11 generations of ancestors by genetic material they contributed to a particular individual. Some ancestors contribute a lot — while others nothing at all. In other words, as you go back in time, the number of your ancestors keeps increasing but not nearly as fast as the number of genealogical ancestors. Look closely at the sixth generation, and you will see some strong contributors of genetic material — and many weak ones…

This basic error in understanding the test results was compounded by the RNC’s reference to the 2014 New York Times article, which was about a genetic profile of the United States, based on a study of 160,000 people drawn from the customer base of 23andMe, a consumer personal genetics company. With reporters believing that Warren’s genome was only as much as 1.56 percent Native American, the article’s line that “European-Americans had genomes that were on average 98.6 percent European, .19 percent African, and .18 Native American” made it appear as if Warren’s sample was even smaller than that of the average American.

Not so. Remember we said that the Bustamante study said she had 10 times more than the individuals from Utah? That’s the relevant statistic, indicating that her claim to some Native American heritage is much stronger than most European Americans.