DNA Results

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Lineages and Results of Y-chromosome DNA Testing for Surname CARMACK


Click here for a chart of the results

Carmack Family Groups: I have organized the results into groups that have close matches.  Thus far we have 5 Carmack Family Groups and another “ungrouped” list. These grouped test participants are considered related if they have at least 10 of 12 markers, or 23 of 25 markers, or 33 of 37 markers that match exactly. I have highlighted those markers that do not match within each group.

FTDNA states that from their observation of 1000's of samples that some markers change, or mutate, at a faster rate than others. While that actual 'faster rate' has not yet been definitively calculated, not all markers should be treated the same for evaluation purposes.

The markers in the red columns have shown a faster mutation rate than the average, and therefore these markers are very helpful at splitting lineages into sub sets, or branches, within family trees.

Explained another way, if you match exactly on all of the markers except for one or a few of the markers that have been determined mutate more quickly, then despite the mutation this mismatch only slightly decreases the probability of two people in your surname group of not sharing a recent common ancestor.

Using DNA Results to Find Ancestors

Most of us are researching our Carmack ancestors -- trying to document at least one more generation back in the chain. The difficulty is getting past brick walls created by lost, burned or never-existing records of births, deaths, marriages etc. Hopefully our DNA project will help you get past your brick wall. How can that happen?

Genetic genealogy can substantiate the known, paper genealogy and help prove that two or more individuals, with the same surname, are connected by a common ancestor.

Estimating when that common ancestor actually lived is left down to mathematics and statistics. Studies show that although a mutation at any particular marker is a random event, it is expected to change roughly once every 500 generations (based upon 25 years per generation). It is like a ticking clock, although this DNA clock doesn't always chime right on time.

The simple step is to find a match between your Carmack DNA and that of another Carmack family who has a documented family tree that precedes your own documented tree. Then you can focus on the missing link between your family and the family with matching DNA. The DNA results will not tell you who links your tree and that of the family with matching DNA, but it will tell you that your families have a common Carmack male ancestor -- what geneticists call the Most Recent Common Ancestor (MRCA).

What constitutes a match?

  • For 12 markers: 8 or less is a non-relative; 9-10 means only a small chance of a relationship; 11-12 means a possible relationship.
  • For 25 markers: 20 or less is a non-relative; 21-22 means only a small chance of a relationship; 23-25 means a high probability of a relationship.
  • For 37 markers: 30 or less is a non-relative; 31-37, please see this chart at FTDNA.

Here is a Table showing the times back to the Most Recent Common Ancestor (MRCA). Those numbers are based in the latest results of the mutation rate study conducted by the University of Arizona. For example, with 37/37 (all 37 markers match), there is a 50% probability that the MRCA was no longer than 2 generations, and a 90% probability that the MRCA was within the last 5 generations. Compare these with 25 and 12 -- with 25 markers, there is a 50% probability that the MRCA was within the last 3 generations, while with 12 markers, there is a 50% probability that the MRCA was within the last 7 generations. 

Probability for Most Recent Common Ancestor (MRCA)

Number of matching markers

50% probability
that the MRCA was no longer than this number of generations

90% probability
that the MRCA was no longer than this number of generations

95% probability
that the MRCA was no longer than this number of generations

11 of 12




12 of 12




23 of 25




24 of 25




25 of 25




35 of 37




36 of 37




37 of 37




The trick is to reduce the uncertainty in the determination of that MRCA until you have identified the individual who is the father of both of your family lines. The ideal process starts with a verification of your own family line of DNA by having distant male Carmack cousins take either the 12, 25, or 37marker DNA test. By proving that they both carry the exact same Y chromosome DNA, you have a solid benchmark which you can compare with the results from other Carmack families who do the same.

As you find Carmack families with matching DNA, you must map them to your own family tree and history. The degree to which your DNA matches determines how far back you probably shared a common ancestor.

As more Carmack males participate in the DNA testing, the number of potential matches for your DNA increases. The more matches you find, the closer you can pin down the MRCAs for you and the matches that you find. Creating an ancestry map like the one in the above figure will help you know when you have identified each MRCA.