It is a pleasure to extend a hearty welcome to our newest members:
- Paul Richardson
- Clyde E. Richardson
Paul Richardson comes to us courtesy of FT-DNA and WOW, we have another exact 37 marker match. Congrats to Fred
and Paul. Unfortunately, we don't yet have an email address for Paul.
Gary, FT-DNA reports they're working on your next group of markers and hope to have results soon (dates slip sometime).
Will keep an eye on things and email them if results not reported soon.
Over the last couple of months, several of you have written me requesting insight into evaluating the results, in particular,
mutations and marker mis-matches. Believe you will find the following information enlightening, I certainly did.
Understanding your Results: Y DNA Mutations
When Y DNA results show several mutations in a family tree, this may indicate a potential problem with the family history
research, and this situation warrants investigation.
Mutations are random events. Mutations are estimated by the scientists to occur every 500 generations per Marker.
When there appears to be a high level of mutations in a family tree, the situation should be thoroughly investigated. One or
more mistaken connections to your family tree will typically result in a higher than expected mutation rate. A mistaken
connection would be where a branch was connected to the family tree in error. This situation can easily occur as your
research moves back in time, and the documentary evidence is weak, insufficient, or circumstantial evidence is used.
Often, as the family tree goes back further in time, it is more and more difficult to find adequate genealogy evidence to
make connections. Connections are sometimes made based on insufficient evidence, such as a person with the same
surname being in the same location. DNA testing will often uncover these mistaken connections.
For example, consider two families residing in Colonial South Carolina with the same last name. It would be easy, though
not necessarily accurate, to assume that they are related.
To illustrate the situation, we have a family tree that has been traced back to a father, John, and his 6 sons. The sons are
Thomas, William, Stephen, George, James and Robert.
A descendant of Thomas and Robert participated, and took a 37 Marker Y DNA test. The result was a 34/37 match, or a
genetic distance of 3. The common ancestor, John, was born about 1726.
If the family history researcher stops at this point, they will never uncover the true situation.
Further investigation and testing is recommended. It is recommended that additional participants be tested to determine
the ancestral result, and to identify the source of each mutation.
If in doubt as to whether to investigate a situation, let's take a quick look at FTDNATiP.
For the above two participants, FTDNATiP shows the following:
100 Yrs. 200 Yrs. 300 Yrs. 400 Yrs. 500 Yrs. 600 years
12.41% 48.13% 77.07% 91.57% 97.25% 99.18%
The common ancestor occurred in about 1726, or about 275 years ago. According to the results from FTDNATiP, we aren't
even in the 90 plus probability range in the 1700's. FTDNATiP is indicating that the situation needs further investigation.
We then enter into FTDNATiP the genealogy evidence that the common ancestor did not occur in the last 9 generations.
The revised report is shown below.
225-325 Yrs. 425 Yrs. 525 Yrs. 625 Yrs. 725 Yrs. 825 Yrs.
55.80% 83.74% 94.71% 98.42% 99.55% 99.88%
The probability of the common ancestor has decreased for our time period of 275 years ago. Investigation of the situation
is definitely required.
A descendant of each of the other 4 sons of John were then tested.
There are now 6 results, one result representing each son of John.
Four participants are a 37/37 match, one participant is a 36/37 match, and the other participant is a 34/37 match.
The result where the 4 participants are a 37/37 match is the ancestral result. Therefore, the additional testing easily
identified the ancestral result.
The participant with the 36/37 match had one mutation. It would be possible to determine the source of the mutation for this
participant by testing other descendants of the son George.
To select a participant to test to determine when the mutation occurred, examine the branch of the tree for the son George.
The objective is to find a direct male descendant who comes off the branch half way from George to the participant.
Testing this person will tell you if the mutation occurred before or after this juncture.
If the new participant has the mutation, the mutation occurred before the juncture where his branch connects to the tree of
George's descendants. If the new participant doesn't have the mutation, the mutation occurred after the generation where
his branch connects.
This process can be repeated until the source of the mutation is identified, which is also known as resolving the mutation.
The next item to consider is the participant who has a genetic distance of 3, or is a 34/37 match with the other 4
descendants. This result indicates that there is a problem that needs investigation.
The participant whose result has 3 mutations is a descendant of the son Robert. The first step would be to test another
descendant of Robert, by a different son of Robert. Robert had 3 sons, Thomas, William, and Richard. The initial
participant was from the son Thomas. A participant who descended from either Richard or William would be tested.
A descendant of Richard was found and participated. His result was a 37/37 match to the result of the other participant
from Robert's branch. Therefore, this participant was also a 34/37 match to 4 participants representing the other sons of
John.
To summarize, at this point in the testing, the results are:
4 participants who are a 37/37 match to each other, each representing a son of John;
1 participant who is a 36/37 match to the above group; and 2 participants who are a 37/37 match to each other and a 34/37
match to the group of 4
The evidence is overwhelming. Robert could not be a son of John, and there is an erroneous connection in the family tree.
The DNA evidence has identified the ancestral result for Robert, as having 3 mutations when compared to the ancestral
result for John, who is assumed to be his father.
This assumption is incorrect. The DNA evidence shows that Robert and John are distantly related, perhaps in the time
frame of 1300-1500. It is probably just a coincidence that they are in the same geographic area in the 1700's.
Investigating mutations is an important step, both to determine the ancestral result, and to investigate potential mistaken
connections.
It may be disappointing to find an mistaken connection in your family tree. Finding and correcting a mistaken connection is
better than passing down to future generations a family tree with errors.
Good Luck With Your Research,
Warm regards,
DeLores
