DNA Results
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Lineages and Results of Y-chromosome DNA
Testing for Surname CARMACK
and Variations, such as: CORMACK,
CARMICK, CORMICK, MacCCARMACK, MacCORMACK,
McCARMACK, McCORMACK, etc.
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?
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 |
90% probability |
95% probability |
|
11 of 12 |
17 |
39 |
47 |
|
12 of 12 |
7 |
23 |
29 |
|
23 of 25 |
11 |
23 |
27 |
|
24 of 25 |
7 |
16 |
20 |
|
25 of 25 |
3 |
10 |
13 |
|
35 of 37 |
6 |
12 |
14 |
|
36 of 37 |
4 |
8 |
10 |
|
37 of 37 |
2 |
5 |
7 |
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.