The 8 Best Ancestry DNA Tests
How Ancestry DNA Tests Work
Most cells in your body contain hundreds of mitochondria or more.
Mitochondrial DNA is passed from mothers to their children, which is why services testing it are often called maternal origin tests.
There are a few different types of ancestry DNA tests on the market. Generally speaking, they fall into three categories; autosomal, mitochondrial, and Y-chromosome tests. Each type works a bit differently, and some methods are better than others at detecting certain traits and origins. All tests begin the same way: with the collection of a DNA sample. This can be done using a cheek swab, a spit sample, or with a special mouth wash or chewing gum. If collected at home, the sample must then be sent to a lab for testing.
Autosomal tests look at the 22 pairs of chromosomes not associated with gender, in order to trace both matrilineal and patrilineal ancestries. These chromosomes carry traits from distant relatives on both sides of a family. The data collected from them enters a database used to find similar patterns among other individuals, called matches. Testing companies typically set thresholds for the length of a DNA strand that constitutes a match.
The primary purpose of an autosomal test is to determine whether you are related to another specific individual, or to find relatives you don't know about. Some companies also provide ethnicity estimates based on your matches and where in the world the patterns found in your DNA are most common.
Mitochondrial DNA is passed from mothers to their children, which is why services testing it are often called maternal origin tests. Most cells in your body contain hundreds of mitochondria or more. Mitochondrial DNA contains far fewer base pairs than the full human genome, so it's easier to pinpoint differences between two individuals' tests. The tests can be used to find one's maternal ancestors or locate their ancestral heritage on their mother's side.
Y-chromosome tests are only available to men, as women have two X chromosomes. As a result, they track patrilineal ancestry, and are often called paternity tests. These tests are some of the most accurate when it comes to determining a person's lineage, because the Y-chromosome barely changes when it is passed from one generation to the next. They can be used to determine whether two people are related on their father's side, as well as how many generations prior a common relative existed. Like maternal origin tests, Y-chromosome tests can also be used to determine the pre-colonial ethnic groups of which one is a descendant based on the haplogroups found in their DNA.
Many commercial tests combine some or all of these methods to give customers a more nuanced understanding of their lineage. Only by analyzing both sides of your family can you determine your true heritage, and the more data you test, the more accurate the results will be.
Why Get Your DNA Tested?
DNA tests of all kinds have exploded in popularity in recent years. The reasons for getting tested vary widely from one individual to the next, but generally fall into one of two categories: an interest in personal ancestry or an attempt to find a common relative with another individual.
If someone you're related to has taken a DNA test, for example, your results will more than likely match with theirs, and most services will let you know.
Americans tend to take a particular interest in DNA tests because, with the exception of the roughly five million people who know of their Native American heritage, the vast majority of people in this country came from somewhere else. Even those with native ancestry have more than likely been displaced by American colonialism, and so determining to which of the over 500 recognized tribes they belong may be a priority for them as well.
While Americans whose families emigrated to this country in recent generations may know a fair bit about where they come from, it's safe to say that many people don't. Even among those who think they know everything about their own heritage, there is a good chance that there is information they don't know, or that's been lost in intergenerational translation.
Of course, there is also a sad history of people brought to this country with their family histories intentionally erased. There were roughly 12.5 million African people brought to the Americas between 1525 and 1866 under the slave trade. An ancestry test can help their descendants determine where their families lived before being forcibly removed from their homelands.
Whether it's the impetus for taking a test or an added bonus, many DNA tests can also help people find relatives they don't know about. If someone you're related to has taken a DNA test, for example, your results will more than likely match with theirs, and most services will let you know. They can also be used to test whether or not you are related to a specific individual.
The Complicated Politics Of Heritage
Everyone has a different understanding of the question, "Where are you from?" The intention behind the question also varies based on who is asking.
The key to knowing where you're from is actually understanding that you're not really from anywhere.
To use myself as an example, I am from New York City, but I was born in Jerusalem. My father's parents are Holocaust survivors from Poland, while my mother's family has been in America for a few generations. I believe they came over from Eastern Europe, specifically Russia, but I am not sure exactly where. To make matters more confusing, Russia looked quite different 150 years ago than it does now.
Beyond the intricacies of family history, the biggest problem with understanding heritage is that the human race has been moving around since its formation. Even the borders we've drawn to designate countries change frequently. If you go back far enough, for example, there was no Europe, so what does it mean to call yourself European?
The truth is that, if you go back far enough, we're all from the landmass now known as Africa. The best DNA ancestry tests attempt to combat the confusion of race, ethnicity, and countries of origin by focusing on historical migration patterns. The key to knowing where you're from is actually understanding that you're not really from anywhere. Your relatives have been all over the place, which is why your ancestry test results might be all over the place. as well.