Best Y-DNA Test

Everything you need to know about Y-DNA testing for genealogy
Marc McDermott

DNA testing is a popular way to uncover your family history. It can connect you with relatives and break down walls in your research.

To dig deep into your direct paternal line, the best choice is a Y-DNA test, and when it comes to genealogy, the best Y-DNA tests out there are from FamilyTreeDNA (FTDNA). They’re also the only company of the big five to offer dedicated Y testing and the only company that provides matches.

Y-DNA testing companies

There are a few different options when it comes to Y-DNA testing. Naturally, prices change from time to time. Keep an eye out for sales and promotions to get the best deal possible.

FamilyTreeDNA

FamilyTreeDNA offers three levels of Y-DNA STR testing: Y-37, Y-111, and Big Y-700 (Big Y also tests SNPs). The number refer to how many markers the test examines. The more markers, the more useful the results will be. The 67 marker test is no longer offered, however, you can upgrade to this test if you start with the 37 marker test. Most people looking to test for genealogical purposes should start with the 37 marker test since this will give you a list of matches. From that list, you can see how many markers each of your matches has tested. If you have a few strong matches at 37 markers who have tested at 67 or 111, you should consider upgrading your test.

LivingDNA

LivingDNA tests the most number of Y SNPs among the big five autosomal companies and should, in theory, give you the most specific haplogroup designation. But as mentioned above, this is not always the case. So if Big Y from FTDNA is not in your budget, LivingDNA’s standard autosomal test might be the next best thing for haplogroup assignment.

23andMe

23andMe will test the Y-chromosome as part of their autosomal test, but only enough to tell you your haplogroup. Their test does not allow you to compare your results against other users to find distant paternal ancestors.

AncestryDNA

Ancestry.com unfortunately does not offer Y-DNA testing at this time. But they do actually “test” the Y chromosome and supply the results if you look at your raw data. The amount of SNPs roughly half of what 23andMe reports and about 20x less than LivingDNA.

Different tests, different results

There are three DNA tests used in genealogy:

  • Autosomal DNA comes from all of your ancestors, so it gives you a broad picture, but can only take you back 400 years at best.
  • mtDNA comes from your direct maternal line (your mother’s mother’s mother), and can trace origins and migrations through thousands of years
  • Y-DNA comes from your direct paternal line (your father’s father’s father), and reaches back many generations, though not as far as mtDNA

Each test provides different information about your family tree, so having all three done can be very helpful. More on the best DNA tests here.

What is Y-DNA?

Human DNA contains 46 chromosomes in a double strand, so there are 23 pairs. Autosomal DNA tests examine the first 22 pairs. The 23rd pair consists of two X-chromosomes (for women), or one X- and one Y-chromosome (for men). Y-DNA tests look specifically at the Y-chromosome.

The first 22 chromosome pairs are a mixture of DNA from both parents, but because only men carry the Y-chromosome, they pass it to their sons with little or no change. That’s important, because it means a man’s Y-DNA is going to be extremely similar if not identical to his male ancestors going back for many generations.

Can a woman do a Y-DNA test?

Women don’t have a Y-chromosome, so they can’t take a Y-DNA test. But that doesn’t mean they can’t trace their male ancestors.

The workaround is easy: convince your male relatives on the direct paternal line to get tested. Brothers, father, uncles, cousins – any of them can help you trace your ancestry through Y-DNA testing. The only male relatives women can’t use are their sons and grandsons, because they carry a Y-chromosome from their father’s line, not their mother’s.

How do you test the Y chromosome?

Having a Y-DNA test done is easy. Just follow a few simple steps:

  1. Pick a company that offers the test and follow-up support you want, such as FamilyTreeDNA, and order your kit.
  2. Once you receive your kit, follow the step-by-step directions included to gather a DNA sample.
  3. Activate your kit online so you can receive your results, then mail the kit to the lab in the box provided.
  4. The hardest step: wait. It usually takes the lab 6 to 8 weeks to process your DNA sample. As soon as they’re done, you will receive an email with directions to access your results.

The science behind the test

Very briefly, your DNA is made up of more than three billion nucleotide base pairs. There are only four different nucleotides (abbreviated A, C, G, and T), so it is the patterns of these nucleotides that let DNA do its work.

Autosomal DNA testing, the most common kind used in genealogy, relies on single-nucleotide polymorphisms, or SNPs. By comparing up to 700,000 points of DNA between two samples, they can estimate how closely two people are related, as well as ethnicity.

Y-DNA tests work differently. They look for markers, or Short Tandem Repeats (STRs), which are places where the same pattern of nucleotides shows up a multiple times in a row. For example, the sequence TGCGACGACGATTG has the sequence CGA repeated three times in a row. The more of these markers that match between two men, the more closely related they are.

A man is often an exact match for his father, grandfather, great-grandfather, and so on. However, DNA mutates gradually over time. Over many generations, these changes add up. So, while two second-cousins who share the same great-grandfather might be exact matches, fourth- or fifth-cousins may not be exact matches. But they will be very close.

What a Y-DNA test will tell you

The accuracy of a Y-DNA test depends on how many markers the test examines. Some tests examine as few as 12 markers, which can be used to disprove a relationship, but not much more than that. Others look at up to 700 markers, letting them very accurately determine that a relationship exists, and even narrow down how far back it goes. All Y-DNA tests also provide information about your haplogroup, although the STR tests can only estimate the haplogroup.

Y-DNA haplogroup

A haplogroup is an ethnic group of people who are genetically related to one another either through their maternal line (mtDNA haplogroups) or their paternal line (Y-DNA haplogroups). Historically, that means they lived in the same area for a long time. Knowing your haplogroup can help you narrow down where your ancestors lived hundreds or even thousands of years ago.

Each haplogroup begins with a letter, followed by one or more numbers and letters. It’s very important to note that, while both Y-DNA and mtDNA tests identify haplogroups, they are not the same, even if they use the exact same label. Learn how to find your haplogroup.

The 37, 67 and111 Y-DNA tests from FamilyTreeDNA are STR tests and can only estimate your haplogroup. Only SNP testing can actually confirm it. For that, you can either upgrade to the Big-Y test or purchase individual SNP tests from FamilyTreeDNA.

It’s worth noting that both 23andMe and LivingDNA tests will also look at the Y-chromosome and give you a haplogroup designation. LivingDNA should give you a more specific designation since they test many more SNPs than 23andMe (nearly 10x more). But since they don’t both look at the same SNPs, it’s possible that 23andMe will be more specific (as was the case for me).

To go even deeper and confirm the most specific haplogroup possible, you’ll need the Big Y test from FTDNA.

Surname groups

Y-DNA is passed down from father to son. So are surnames, or family names. That means Y-DNA testing and surname societies go hand in hand. Both of them trace their lineage back through the direct paternal line.

Connecting with a surname society or research group means connecting with dozens or even hundreds of enthusiastic genealogists who are studying the same ancestors as you. That creates a tremendous opportunity to share research, break down brick walls, and quickly uncover your roots.

Many surname groups have “family reunions” as well, where distant cousins from all over gather to meet each other and explore their family heritage.

FamilyTreeDNA gives you the option of making your results (semi-)public. If there are other people with matching Y-DNA test results, you and they will be able to find and connect with one another through the website. But your results won’t be visible to the whole world, only to other family historians with matching DNA. This is a great way to find living relatives studying the same family tree as you.

Your results may also point you in unexpected directions. While many surnames have been passed down through families, other people have had surnames assigned to them. This is especially true for populations who didn’t use surnames, such as Native Americans or African American slaves.

Other surnames changed either gradually over time, or suddenly, such as when immigrants arrived in the U.S. Many new arrivals changed their surnames (or had them changed by immigration workers) to sound more British.

Your Y-DNA results can help you break past these barriers to discover Eastern European, Native American, African, or other roots you never expected.

Can Y-DNA prove paternity?

Many people who were adopted look to DNA tests to find their biological parents. When it comes to Y-DNA tests, there some good news and some bad news.

The good news is, a Y-DNA test can 100% rule out paternity. If two men do not have matching Y-DNA tests, they cannot possibly be father and son.

What if their tests are an exact match? Unfortunately, that does not prove paternity, it just means they have a common ancestor. Because Y-DNA changes slowly over time, that ancestor could easily be five generations back, or even more.

So while Y-DNA testing cannot be used to prove paternity for an adoptee, it can certainly be used to disprove. To determine paternity, you need to look to an autosomal DNA test.

Start digging today

Y-DNA tests have their limitations. Only men can take them, and they only trace your direct paternal line. But they can still tell you plenty.

Haplogroups let you learn your distant origins going back thousands of years. Sharing your results lets you connect with much more recent relatives who trace back to a common ancestor. Both of these can give you what you need to continue your genealogical search.

Your best choice for Y-DNA testing is FamilyTreeDNA. Take a look at their options and start tracing your paternal lineage today.

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