What’s a Good DNA Ancestry Test?

Many genealogists are looking for a good DNA ancestry test that will help them expand their family trees. Likewise, many adoptees are using DNA to uncover their biological families.

For these ancestry purposes there are just three tests to consider. Fortunately, all three can be obtained from one DNA sample and through one company-- Family Tree DNA.

There are a few other companies that offer some of these tests. But no other company currently offers all three. Plus, Family Tree DNA (FTDNA) is used by 90% of the genealogists that do genetic genealogy tests. So you can’t go wrong using them.

If you want to read a more complete summary of why I prefer this company see my FTDNA Review page.

Note that the DNA tests discussed on this page are covered in more detail in the Family Trees section of this web site.

The Y-DNA Test of Your Paternal Line

This DNA ancestry test looks at the Y chromosome, which passes from father to son, generation after generation, follows the paternal line shown in the diagram below.

If you’re a woman, you can’t take this test yourself. But you can test a male in your paternal line, e.g. your brother, your father, your father’s brother, or a son of your father’s brother.

Basically, the Y-DNA test will provide you with the names and email addresses of men you match. These men share a common paternal line ancestor with you. Knowing that, you can often compare your family pedigrees and determine exactly who that common ancestor must have been.

The match between your DNA and your paper trail then provides absolute confirmation that the paternal line of your tree is correct as far back as that common ancestor.

Your test results will also predict your haplogroup. This will tell you in what parts of the world your ancient paternal line ancestors lived thousands of years ago. Certain haplogroups can even confirm the presence of specific ethnic groups in your paternal line.

Since surnames typically remain unchanged down the paternal line, many adopted males taking the Y-DNA test will identify the last name of their birth father. Currently, about 25-30% of adoptees are discovering this surname immediately from their initial results. That percentage will grow as the database continues to expand.

The mtDNA Test of Your Maternal LIne

This DNA ancestry test looks at the mitochondrial DNA that passes down from mother to child. Mothers give this particular DNA to all their children, so both men and women can take the test. Yet only daughters can pass on their mtDNA.

As a result, the mtDNA traces the maternal line of a family. See the following diagram.

Like the Y-DNA test, the mtDNA test will provide you with the names and email addresses of people you match.

It also predicts your maternal haplogroup, which is different from the paternal haplogroup discussed above. As with the Y-DNA test, there are haplogroups that can confirm the presence of specific ethnic groups…but this time in your maternal line.

In my opinion the mtDNA test is the LEAST useful DNA ancestry test for most people. Unless you can easily afford to do all three tests, I suggest you invest in either or both of the other two tests before you consider this one.

That’s because even your closest matches on the mtDNA test may result from a common ancestor that lived hundreds or thousands of years ago.

Furthermore, the longstanding custom of females taking the surname of their husband makes maternal line matches much more difficult to connect genealogically.

The Family Finder Test for ALL Your Ancestors

The newest DNA ancestry test—and in many ways the most exciting—is the Family Finder test. A SNP-based autosomal test, this test looks at more than 700,000 locations in the DNA you inherited from both parents.

This means the people you match could share a common ancestor with you in ANY branch of your family tree back at least five generations or so. Matches labelled "speculative" may even reach back as far as ten generations.

The following diagram indicates that ALL lines can produce matches. The actual reach back in time will usually go farther than shown in this simplified view.

Since Family Finder is NOT limited to just your paternal or maternal lines, you will most likely get many more relevant matches than you would get from either of the first two tests.

As it does with its other tests, Family Tree DNA provides you with the names and email addresses of your matches so you can contact each other to compare family trees.

Family Finder also provides a chromosome browser so you can see the exact regions of each chromosome where you and selected matches share long strings of matching DNA.

Designed with genealogists in mind, Family Finder allows you to post lists of surnames or even post your family tree via a GEDCOM file. These tools can help point you and your matches in the right direction as you research your connections.

Finally, this DNA ancestry test includes a report called Population Finder. This is the best option available for measuring a person’s overall ethnic ancestry.

To see the current prices on these three DNA tests follow this link to the Family Tree DNA web site.