mtDNA matches are separated into different levels based on the amount of mitochondrial DNA (mtDNA) being compared. Generally speaking, the more mtDNA you share with another person, the more closely related you are to them.
mtDNA tests have evolved over the years, and focus on three regions of mtDNA: Hypervariable Region 1 (HVR1), Hypervariable Region 2 (HVR2), and the Coding Region. The very first direct-to-consumer mtDNA test sequenced HVR1 only. As technology improved and more panels were added, the other two were eventually added.
Depending on the date your match(es) tested, they may have tested only HVR1, HVR1 and HVR 2 (which we called mtPlus), or the entire mitochondrial genome. The test we now call mtFull Sequence has been referred to as the Full Mitochondrial Genome, Full Mitochondrial Sequence, or occasionally just the Full Genome.
mtDNA Match Limits
The goal of mtDNA matching is to find testers who share a direct maternal ancestor within a timeframe that is genealogically or historically relevant. To filter out matches beyond those timeframes,we set a limit on the number of mutations allowed between two people for them to appear as a match.
The Coding Region of your mitochondrial DNA is much larger than the HVR1 and HVR2 regions combined. Because HVR1 and HVR2 are relatively small segments, our system only displays perfect matches for those levels—meaning both testers must have the exact same mutations.
However, when comparing the much larger Full Sequence, we allow for up to three (3) mutational differences. Because this 'Full Sequence' threshold is more flexible than the 'perfect match' requirement for HVR1, you may find matches at the Full Sequence level who do not appear on your HVR1 or HVR2 lists.
Filtering by Match Level
Match levels are displayed on tabs labeled Coding Region, Hypervariable Region 2, and Hypervariable Region 1, and the highest level you’ve taken will be displayed by default, whether you have matches at that level or not.
If your matches have not tested to the same level that you have, you will need to navigate to the shared match level.
For example, if you have a mtFull Sequence Test (which includes HVR1, HVR2, and the coding region) while a match has a HVR1 only, you will need to navigate to the HVR1 match level to see that match.
You can toggle between match levels by clicking on each region at the top of the list. The number in parentheses after the match level indicates the number of matches you have at that level.
Sorting Matches
The default order for your matches is based on Genetic Distance. This means the matches with the fewest mutational differences appear at the top, as these are your closest genetic connections. If you would like to view your list differently, you can use the Filter icon to narrow your results or the Sort By icon to change the display order.
For more details on how to sort and organize your matches, click here.