Male Descendancy Tree

NOTE: Abbreviations used throughout this page are described within the text or in the Pseudo-Family section.

• Single Subject Tested per line:

• Additional Subject on one line:

• Two Subjects Tested per line:
        a) Genetic Distance 2 or less
        b) Genetic Distance 3 or more

• More than two Tested per line:

• Determining the generation of mutation:

• Concluding Remarks:

• Examples and results of lines tested:

• Pseudo-Family Descendancy used for explanations:

Summary of Abbreviations used:

1. DNADCA: DNA Determined Common Ancestor. Results of DNA analysis has determine that a common ancestor.

2. EKCA or EKCA-x: Earliest Known Common Ancestor or Earliest Know Common Ancestor for line x

3. Com0: Time of the EKCA

4. others as described within the text.

Single Subject Tested:
The first example shown here is for the case where only one member from each of several lines has been tested and one is trying to determine as much as possible about how the different family lines diverged from the time of the DNA Determined Common Ancestor, DNADCA. The results shown in the following table are actual values for a group of people identified as Branch-One Krause. As each new sub-branch was found by DNA results, they were given a sub-branch letter to identify them from the other sub-branches.
The following quote is from the FTDNA Group Administrator info. "The DYS markers in red have shown a faster mutation rate then the average, and therefore these markers are very helpful at splitting lineages into sub sets, or branches, within your family tree. "

If one uses the assumption that more recent changes are where only one person shows a change in an Allele value at DYS#n then the numbers shown as bold and a yellow background indicate the three most recent changes. Using this assumption then a BASE SET of Allele values can be shown as indicated in the last row of the table. As more persons are tested and found to have a DNADCA then this table will hopefully show more insight into how the family lines diverged.
More information on Branch-One Krause Sub-Branches and the Genetic Distance is available at the following page on Analysis of DNA results.
With only a singe person per line being tested then it is impossible to say if the changes noted have been before or after the time of the EKCA-branch-line. To determine this, a second person from each line must be tested as explained in the next section.
An attempt has been made to predict a Possible Divergence of these lines for the Sub-Branches A-G. A new diagram is required as additional members lines are added but becomes more complex and the usefulness becomes questionable.
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Additional Subject Tested on One Line:

By finding another subject who is from a known lineage where the two persons tested have the greatest number of generations back to their Earliest Known Common Ancestor, EKCA, then the maximum information can be learned about any changes in Allele values that have occurred in the time since this EKCA.
The following discussion is based on the pseudo-family  shown in the outline report and the line chosen is B with the first person tested being the one called H Surname, the second one tested then could be J or K Surname. If line C  Surname where the one used then the second person would be L or M Surname.
The following discussion shows the different Cases that exist for this kind of testing when the Genetic Distance is n (GD-n).

Case GD-1 #0:
The second person matches exactly with the other person tested from their EKCA.  The change in Allele has been in the other line and the time is unknown as it could be any time since the Common Ancestor.

Case GD-1 #1:
The second person tested matches exactly with the other line. The change in Allele has been in the line where the two have been tested and the change has been since the EKCA for that line.

Case GD-2 or more #2:
Since two Allele values are different then the same method shown in Case #0 and #1 can be applied for each DYS marker. However, as stated above in Case #0 it is impossible to determine when the change occurred then a second person must be tested from the other line as shown in the next section.
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Two Subjects Tested per line. GD 2 or less:
The outline report shown below for a pseudo family is an attempt to show how one might possibly go about determining how recent the DNADCA is when two different males have their Y-Chromosome DNA tested and the results show very little or no difference for the results shown for the DNA values. An example would be an exact match for a 12-Marker test and 1-2 different for the 25-Marker and 2-3 for the 37-Marker test. These results then indicate the presence of a common Ancestor shown below as "Common-Ancestor Surname, DNADCA" however, the number of generations back to this ancestor is unknown so the person who looks like ?-x is actually an unknown number of generations down to the earliest known common ancestor for each of the descendancy lines shown below(EKCA-B for line B or EKCA-C for line C). The actual number of generations to the persons tested and shown high-lighted in Yellow will only be known by the paper trail that one has found by conventional research methods. The person tested may have a different surname shown in Mauve below and if so, the method of further testing is the same. The designation of the time for the EKCA-x, (x is B, C, or T), is shown as B0, C0, or T0. This time is the generation at which a known ancestor has two or more sons and is used in the Case Explanations shown below.
 

Case GD-0 #0:  Exact match
An exact match is shown between two or more subjects indicating a genetic distance of 0. If only a 12-Marker test has been done then both members need to extend the number of markers tested to 25 or better yet to 37. If the match is 1 or less when 37 markers have been tested then the test should be extended to 67. If the difference remains at zero even for a 76 marker test then the Common Ancestor is more recent and the prediction algorithm used by FTDNA becomes very useful for determining the probable time to the Common Ancestor. This is presented in a table for the persons tested in Branch-One Krause and shows the probable number of generations to the Common Ancestor.
However, it is also possible that the following cases can be considered where the value after the case # is the genetic distance that has been found for the two or more individuals tested for each line.

Case GD-1 #1:

 The challenge is to try and determine if the changes in the Allele value have occurred in the time period Com0-B0, called TB0, or from B0-H0, called TB1, for the person from line B or for the other person from line C where you would be trying to determine if the change in Allele value was from Com0-C0, called TC0, or from C0-N0, called TC1.

If the male descendancy tree shows more then one son for the EKCA then a male descendant from that line should be tested to see what the values are compared to the line that has been tested. For example, if the person shown as H Surname wished to have someone from his line tested then possible candidates are the males shown as J or K who are descendants from the son called E Surname(in all cases, sons of the EKCA should be chosen so as to select lines that diverged the furthest back in time). The same holds true for the other line that has been tested on the C Surname line. Possible persons are L or M in this case.

If the results of a 37-Marker Y-Chromosome DNA analysis shows an exact match for these two males for the same line then it means the Allele changes have occurred in the time TB0 if Branch B is the one being tested or TC0 if Branch C is the one being tested. Conversely, if the results match the person from the other line then the change has been from the time of the EKCA to the person who was first tested in the line for the second person. See notes on the outline report shown below and the next section for further explanation. If the change in Allele value has been recent[TB1 or TC1] and no change prior to the time of EKCA[TB0 or TC0] then the time Com0 from the DNADCA is probably more recent then if the changes occurred prior to the time of the EKCA on either line.
 

After one has tests from other members as indicated above then it may be possible to gain further insight into the time(Com0) of the DNADCA by extending to the 67-Marker tests that have become available recently. By analyzing these results it may be possible to determine how closely connected the two lines are. It is never possible to say with 100% accuracy that two males descended from the same known father as males from a previous generation could show identical results and any connections make would be based on further paper research and not DNA testing. If the changes have been during the time since the EKCA for each line then the time to the DNADCA might be more recent then if the changes have been prior to the time of the EKCA for each line.

If another branch called A Surname is thought to be related then the persons who could be tested are shown as R or S and if the results match as indicated above then they are part of the descendancy from the same common ancestral line.

Case GD-2 #n:

This is much more difficult to determine as the change can be from the time of the DNADCA to the earliest EKCA for line B(TB0) or from the earliest EKCA to the time of the person tested for line B (TB1). Since there are two lines then the following table shows the possibilities for lines B and C with the Allele value changes indicated as the numbers in the columns. If the second person tested for line B has identical results to the two from line C then the change has been in the time TB1. Conversely, if the second person tested has identical results for line B then the change has been in the time TC1. In both of these cases, no changes had occurred in the time TB0 or TC0 indicating that the DNADCA is more recent then if the changes had been in the time TB0 or TC0. These cases, are summarized in the following table:
 

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Two Subjects Tested per line. GD 3 or more:
The methods to be applied for this case are essentially the same as for the case where the GD is 2 or less. With the four persons tested, two from each line then one tries to find markers that have changed in the time since the EKCA and determine which person has had the change. All of the possible cases as outlined in the GD 2 or less will not be shown here as the number becomes much larger then the 9 shown in the table in the previous case. Once all of the changes that have occurred since the time of the EKCA have been determined then the number of changes from the time of the DNADCA to the EKCA may be found to be small in number indicating that the time to the DNADCA is much shorter then first anticipated.

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More than two tested per line:
Even with all the possibilities shown for two tested per line, it is still possible to use the techniques as indicated in Case GD-2 #n to determine when the changes occurred. When more members from each line are tested then this would be the best approach to determining what possible combination shown above was the Allele change that happened in this situation. If the additional person tested for line B has identical results to the majority from line C then the change has been in the time TB1. Conversely, if the additional person tested has identical results for line B then the change has been in the time TC1. In both of these cases, no changes had occurred in the time TB0 or TC0 indicating that the DNADCA is more recent then if the changes had been in the time TB0 or TC0.
If the additional member tested for line B shows a difference greater than one at the same DYS# as a member from line C then the change vs. time is more complex and will not be detailed at this time.

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Determining the generation of mutation:
If all male descendants of EKCA have two or more sons who have living male descendents then it is possible to determine the actual generation that a mutation took place. The method of doing this is to use a binary search method and for the purposes of this example it will be assumed that the generation level of the EKCA is 8. Since one line from a son of this ancestor contains the mutation and the other one does not then the binary number is 0???. Where the  ? marks are the unknown values in the binary number. The process consists of dividing the total number of generations from the EKCA to the present time in half. If a male descendant from the fourth generation is selected for testing then if that person has the mutation the binary number becomes 01??. If the generation just tested was positive then the time range from the fourth to eighth is divided in half. The next test would be to determine if the sixth generation level descendant has the mutation and if they do not then the binary number becomes 010?. Since this last test failed then the time from the sixth to the fourth is divided in half. The final test would be to test the fifth generation level to see if they had the mutation and if they do then the binary number is 0101 which is the generation at which the mutation occurred. From this example it can be seen that with 2 or 3 tests it is possible to determine the actual generation level at which a mutation happened. The 2 test solution would be if the person already tested with the mutation was the one where the mutation occurred.
If the male descendants from the EKCA is not an even power of two as assumed in this case then lets say for example there are six generations then the best would be to take the closest power of two that has the largest value. In this case, the choice would be between two and four when the total generations are divided in half. The process then continues exactly the same as described previously.

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Concluding Remarks:
The Allele values determined from  Y-Chromosome DNA analysis are stated to change on average every 500 years or 20 generations. Since this is an average and the DYS#'s have different probabilities of changing then one cannot say with any certainty when any values changed. Only by doing exhaustive testing of persons who descended from a know ancestor can one determine if the changes have occurred in the time frame since the time of the EKCA. The other possibilities are that Allele values may have changed multiple times and since the change can be +/- then with two changes, one being + and the other - the result is that it appears that no change has occurred. All of these are possibilities but since the changes are all based on probabilities then the probability of this happening may be very small. As more people are tested and the pool of data results becomes larger then more insight into this will become available.
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Examples of line tested that show only slight differences and where the surname is the same or different are found at the following links:
Branch-Three Hodgson
Hodgins Branch-09

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