A Y-DNA SNP test determines your Y-DNA haplogroup.  Knowing how you connect to other people on the Y-tree can help narrow geographical origins and can potentially confirm specific genealogical connections. We encourage you to test as many SNPs as possible for the most rewarding experience. Learn more about our SNP Packs below to get the best deal on SNP testing.

Testing Y-DNA SNP markers places you further down the branch on the Y-DNA haplotree and assists us with scientific research on the Y-tree and for your haplogroup projects. The more people that test their SNPs, the more data points we have to further our understanding of human migration and history. More importantly to you is that SNPs may help in your genealogy and deep ancestry research.

What is the difference between an SNP and an STR?

An SNP is a single nucleotide polymorphism. That means that it is a single, small change in your DNA code. These changes are rare. Once they happen, they seldom change back (back mutate).

An STR is a short tandem repeat. This is a place in your DNA code where a letter sequence is repeated. For example, AGTAAGTAAGTA is three repeats of the sequence AGTA. STRs have a faster mutation rate. When they change, it is an increase or decrease in the number of repeats. STR values change back (back mutate) more commonly.

If you are interested in your ancestry that goes beyond where traditional paper trails end, you should focus on SNP testing. If, however, your primary interest is in the most recent generations of your family history (1 to 15), testing additional STR markers is a good investment.

SNPs offer a definitive answer to a potential relationship. When one person is positive (derived) for an SNP and the other person is negative (ancestral) for the same SNP, they are not related in genealogical times.  On the other hand, if both men have matching SNP results, their STR (short tandem repeat) marker results determine how recently they are related.

How do I know which SNPs make sense for me to order?

Please order SNPs with the help of an expert, if you aren’t sure which SNP(s) will benefit your research.

Before ordering, you should ask the advice of an expert on your haplogroup and subclade. We recommend joining an appropiate Y-DNA Haplogroup group project. You may then consult the administrators.

What is an SNP Pack?

SNP Packs are bundled groups of SNPs relevant to a specific branch of the Y-DNA haplotree and are designed to give you more information for less expense.

You may view the exact SNPs available on your Y-DNA haplotree. Most SNP Packs will include relevant SNPs for your clade, as well as some ‘hidden’ SNPs that are not yet available on the Y-DNA haplotree.  Hidden SNPs are SNPs we are testing to determine if and where they belong on the tree in a specific clade.

Do I have to order a Y-chromosome DNA (Y-DNA) STR test before I take an SNP test?
Yes. If you do not have a Y-DNA STR test, you will not be able to view your haplotree information.

Alternatively, you may first take the Geno 2.0 test and then transfer your results to Family Tree DNA.  You will then see your Y-DNA haplotree and transferred positive SNPs from Geno 2.0. Ordering additional SNPs or an STR test after transferring results from Geno 2.0 is up to you; however, we recommend consulting a Haplogroup project administrator before deciding.