claim they have native american blood

But here methinks I can hear you observe What! Englishmen intermarry with Indians? But I can convince you they are guilty of much more heinous practices, more unjustifiable in the sight of God and man. . . for many base wretches amongst us take up with negro women, by which means the country swarms with mulatto bastards, and these mulattoes, if but three generations removed from the black father or mother, may, by the indulgence of the laws of the country, intermarry with the white people, and actually do every day so marry.

Now, if instead of this abominable practice which hath polluted the blood of many amongst us, we had taken Indian wives in the first place, it would have made them some compensation for their lands. . . . We should become rightful heirs to their lands, and should not have smutted our blood . . .

The Reverend Peter Fontaine of Virginia,
in a letter to his brother Moses,
dated March 30, 1757

There's long been a belief among the many family members on my father's side that my father's grandmother was "part Indian." From what I've gathered, such claims are common in white families in the United States. White claims about what may be just as likely -- being part black -- are almost non-existent.

I would like to know what percentage of Americans who self-identify as white contain non-white blood, but reading around on the topic tells me that any particular statistics are not universally accepted by genealogical and DNA experts.

Also, since so many people who did have African or Native blood and could pass for white did so, only DNA tests for a large percentage of white Americans could provide reliable percentages (but even then, the tests themselves aren't necessarily reliable -- the "Native American" results, for example, could be confused with Asian ancestry, given the geographic origins of Native Americans).

According to a Guardian article by Paul Harris on the increasing popularity of genetic testing, "One-third of white Americans, according to some tests, will possess between two and 20 per cent African genes. The majority of black Americans have some European ancestors." (I've yet to find informed estimates of white Americans with Native American genes -- please tell us in a comment if you know of any.)

Harris points out that "Native Americans are growing in numbers, not because of a high birth rate, but because many Americans are discovering unknown native ancestors written in their DNA."

I doubt the same discovery about African American blood is causing that recorded population to increase. Given the regularity with which white Americans impregnated slaves in order, among other reasons, to increase their "property" (and then going on, in some cases, to sell their own children), and again, given the ability of many light-skinned "black" Americans to pass into white society -- given these and other factors, I would think that DNA tests for whites probably turn up more African American than Native American blood. And yet, few white people who find black blood probably go on to proclaim their black ancestry, while many who find Native American blood do go on to proclaim that ancestry.

I should also note that white people in the United States are not the only ones who hope to find Native American ancestry. Many African Americans seek it as well, and significant interaction between the two groups means that some find it. And many Latino/a Americans, of course, don't have to search far at all to find their Native American roots.

Some of the white Americans who take DNA tests or search census and birth records for Native American ancestry do so in the hopes of claiming financial benefits. As Harris writes,

Native Americans often complain they are swamped by "American Indian Princess syndrome," because every white person wants native DNA in their past. In a world of minority grants, scholarships and Indian gambling rights, any debate over DNA and race could easily also become an argument over resources.

Some of these questing white Americans just want to know "who they are." This strikes me as a a dubious quest -- would finding some Native American or black blood really make a person who was raised white, looks white, and gets taken and treated as white, any more "black" or "Indian"?

It's also clear that most white people looking for Native American ancestry are hoping to establish a more romanticized connection to Indian-ness. A connection based in, and stuck in, the past, much more so than the present.

These are the white searchers (sometimes called "pretendians") who hope to fill up a certain emptiness in their bleached-out, whitened identity, but want little part of actual, ongoing Native American struggles. Many of them will never go to a reservation to experience the results of white genocidal practices, even if they do find Native American blood in their DNA. They're rarely willing to fight for treaty rights, nor help with such contemporary problems as compulsory sterilization or substance abuse. Indeed, they're rarely willing to even acknowledge these problems, or do much of anything else that goes beyond vague, sentimental ideas of supposedly authentic Indian-ness.

So why do a lot of white people cherish the possibility of Native American blood so much more than that of African American blood, even when the latter may well be a more likely part of their background?

I think as with the cherished Native American possibility, their distaste and sometimes even disgust for the possibility of black ancestors is based on received notions from the past, but also on those of the present. Ever since slavery in the U.S. was limited to black people in order to divide them from working white people, they've been the most despised racial group. Any sober look at today's American culture in general -- the primary source of our received notions about other people -- would reveal that disdain for racial minorities continues to be strongest for black people.

Actually, common white notions of American Indians are also largely ingested from current cultural imagery, from "brave" or "noble" team mascots, to the continued predominance of TV and movie images of long-gone Indians over accurate representations of the remaining ones actually living today. As gwen notes in a Sociological Images post on this anachronistic tendency in non-indigenous appreciation of "Indian art,"

This tendency is apparent in other elements of U.S. culture, of course: movies like “Dances with Wolves,” books about “noble savages,” and conflicts over what types of technologies American Indians can use when spear fishing (with non-Indians arguing Indians should only be able to use the methods that their tribes used in the 1800s) all indicate a wider perception that “authentic” Indians should inhabit a time-warp universe in which their cultures and lifestyles have remained basically unchanged since the late 1800s or early 1900s, a requirement we don’t ask of other groups.

As far as I know, no one in my family has taken a DNA test to settle the question of whether we actually have Native American ancestors. If some of my relatives do decide to do it, I hope I get a chance to talk to them about just what it is they're really looking for. I'd also like to know what they plan to do if they find something else.