Family Finder matches are other individuals in our database who have also taken the Family Finder test and who are found to share a common ancestor from ANY of your ancestral lines within the past five generations through autosomal DNA comparison.
Autosomal DNA is a roughly 50/50 mix of DNA from each parent. The 50% received from each parent is random, and no two children (with the exception of identical twins) receive the same combination. An analogy could be shuffling decks of cards: If your mom is a deck of cards, and your dad is a deck of cards, shuffle the two together, then take half the deck. That is the DNA you receive. Shuffle these decks again, and that is the DNA your sibling receives. While you are creating this new deck from the same two source decks, one will have more spades, while another will have more diamonds.
This process, called “random recombination,” occurs every generation. This means that as the generations pass, some cards can be included in the new decks again and again, while others get shuffled out. Generally speaking, after five or six generations, the number of cards from any ancestral deck is so small it is impossible to use for matching. However, you may find cousins who share common ancestry further back than five or six generations if you both share cards that survived many shuffles.
Even at just one generation, you may find you have more DNA in common with one first cousin than you do with another, because of how the decks were shuffled. This creates a range of possible relationships for any given amount of shared DNA and not an exact figure.
Autosomal DNA is measured in a unit called Centimorgans, or cM, with one centimorgan equaling about 100 base pairs on the genome. The maximum number of centimorgans you can share with another individual would be your parent or child at roughly 3,500 cM. Generally speaking, the more centimorgans two people share, the more closely related they are. Due to random recombination, this is not always the case though, particularly with distant matches.
The predicted relationship range for your matches is determined by a few factors. One is the number of centimorgans, and another is the longest block. To revisit our deck of cards analogy, if each parent is a pack of cards, imagine they are a fresh pack with all the cards in order: Ace of spades, then 2 of spades, then 3, and so on. The longest block refers to the number of cards in a continuous stretch. The more generations that occur between you and the common ancestor to a match, the smaller the blocks become, due to the more shuffles. This means you could have a match with fewer overall centimorgans with one match than another, but if the blocks are longer, it may indicate fewer shuffles, and therefore they could be closer. These and other factors all contribute to the range given for a match.
For some ranges, you will see a list of possibilities. An example is “Half Sibling, Uncle/Aunt/Niece/Nephew, Grandparent/Grandchild.” Each of these potential relationships shares roughly the same range of shared cM, so all are listed. The relationship range is a guide to give you an idea of the number of generations on your matches’ trees you should look at to find shared ancestors.
Accessing Family Finder™ Matches
You can access Family Finder Matches from your dashboard or from your navigation bar.
To access from your dashboard:
- Sign in to your kit.
- On your dashboard, locate the Autosomal DNA Results & Tools widget.
- On the Autosomal DNA Results & Tools widget, click the Family Finder Matches button.
To access from your navigation bar:
- Sign in to your kit.
- On the navigation bar at the top of the page, go to Results & Tools > Autosomal DNA > Matches.