The "modal" for any group is just the most common set of marker for that
group. There's nothing mysterious about it and no "experts" saying what the
modal is.
The modal for any group is usually assumed to be the DNA of the common
ancestor of that group. If 15 out of 20 members of a group match perfectly,
that would imply that these 15 have the DNA of the common ancestor, and the
other 10, who are one or two markers off, have that same common ancestor but
some mutations have occurred since that ancestor.
Take away markers 6 and 20 and the modal for all of group 3 in the rest of
the markers is the same. This implies that the two groups have a common
ancestor somewhere back down the line.
What seems to have happened is that there was one common ancestor for all of
group 3, then there was a branching since that common ancestor.
One group probably has the DNA of the common ancestor but somewhere a descendent of
that common ancestor had mutations in 6 and 20 and became a sub-line. Or it
could have occurred in more than one generation; that is, maybe one Pace had
the mutation in 6 and his son had the mutation in 20. Rebecca can correct me
if this is not good thinking.
18 members of 3a have the 14-29 combination in those two markers, so that
defines the modal for that group. In other words, these 18 probably have
the DNA of the ancestor of 3a. 16 members of 3b have the 12-30 combination
in these two markers, making that the modal for those two markers So this
16 probably has the DNA of the common ancestor of 3b.
This thinking only works if the samples are from different branches of the
line. If they all come from one family or cousins, this would not make a
"modal" for other branches of that line.
Now how about those "in between" folks? Can they be an "in between" group?
I don't think so. If 3a has one ancestor and 3b another, how can this group
have an "in between" ancestor?
Besides, there are three descendents of John/Sarah, and two of the three
would be in the "in between" group and the third would not. If the
documentation to John/Sarah is accurate, it would not make sense to put two
of them in one sub group and the other in another.
In addition, all of these "in betweeners" submit lineages that put them in
3b. Surely they are not all in error.
The most likely explanation is that in more recent times there has been a
mutation going from 30 to 29. That could occur even in the present
generation. John probably matched with the modal for 3b but some of his
descendents had mutations in 20.
Now some speculation.
Kit number 8179, Antony Pace of London (he has given
permission to use his name) matches 62/67 with 3a, fairly close at that
large number of markers, and has the 3a modal in those two markers. Could
this imply that 3a carries the DNA of the original ancestor and 3b branched
off from this? This is just a wild guess but speculation can sometimes lead
to meaningful results.
Roy Johnson
TOP of PAGE
PACE DNA STUDY
Sent: Sunday, June 21, 2009
Cc: pace@rootsweb.com
Subject: Re: [PACE] Documentation on Stephen Pace line?
Isn't that the point of taking DNA tests? We will never have full
documentation on some of these early Pace people and we take DNA tests in
order to confirm where to place an ancestor.
BPace
REPLY
Roy Johnson
PACE Family DNA Coordinator
answers saying:
Here is my take on this:
DNA can point but not prove.
Let's say several donors have matching DNA and all of them submit an undocumented line back to an apparent common ancestor.
But it is entirely possible that all of the donors picked up their ancestry
from something someone else posted on the Internet. Thus all of their
lineages could be in error.
So what you have is evidence that this group of donors has a common
ancestor, but until some documentation can be found, there's no telling who
that common ancestor might be.
The John of Middlesex line is an example. We had numerous attempts in Pace
genealogy to trace John back to Richard of Jamestown. DNA immediately
disproved that hypothesis. But then Gordon Pace of Canada matched perfectly
and had documented records to his ancestors in Shropshire.
His documented ancestor had a brother John just the right age to be our John of Middlesex.
That John disappeared from English records after his birth, and our John in
America and Gordon's George in England named five of their children (George
only had five) the exact same given names. Two of the given names were the
parents names of John and George in England.
We still do not have documentation that John of Middlesex was John of
Shropshire. But it is Gordon's documentation that made it possible to
assemble this nearly overwhelming circumstantial evidence. Without his
documentation all we would have is a theory.
There might be a bit of leeway if the different donors all got their
information from family sources, did not consult one another, and agree on
the common ancestor. This would be strong circumstantial evidence and would
make what is called in historical research a "strong hypothesis", as the
sources agree and there is no contradictor data. But it still cannot be
called a fact.
The Frederick Pace of Wales line is another good example. DNA proves that
these donors are a separate Pace line and have a common ancestor. The
existence of Frederick is hard to deny since all donors have him in their
family sources and his name appears in other sources as well, but no
documentation on Frederick has been found, and whether he was from Wales or
(quite possibly) from the "border marches" next to Wales is unproven.
This is just my thinking on the subject.
Roy
TOP of PAGE
The DNA study by itself cannot prove that anyone is a descendant of Richard Pace of Jamestown.
The PAPERWORK has to first prove that a particular line of Paces are descendants of Richard of Jamestown
then the DNA study can be used to determine if other participants share a common ancestor with the participants who can prove their lineage to Richard of Jamestown. As there have been questions created about the long-accepted link between Richard Pace of NC being the descendant of Richard of Jamestown, these questions have to be resolved with the paper trail before anyone can say that DNA has shown they are RELATED to Richard of Jamestown.
In fact, we have very little DNA evidence for most of the Pace lines. The DNA study has been very effective in determining that there are at least two main groups of Paces in the United States - and also other Pace lines which have not had as much research performed and WRITTEN about.
We have learned that
- the John Pace of Middlesex line,
- the majority (or the most written about) of the NC Pace lines,
- and the Michael Pace/Pees lines
are very distinct lines
and have no common ancestor in "modern" times.
But, as for Group 3 of the Pace DNA study, we really have very little representation of family lines in the DNA project.
GROUP 3a
Most of the Group 3a participants are descendants of WILLIAM PACE and RUTH LAMBERT - a line that has several theories of the lineage back to the early Richard Pace of NC.
Other participants are from
- two different HARDY PACES,
- an unconnected GEORGE PACE,
- and TWO PARTICIPANTS
whose DNA results can only give us the *ancestral* DNA results for RICHARD PACE whose wife was ELIZABETH CAIN
- and not any further back.
GROUP 3b
Group 3b is not any better in representation.
Basically there are three lines represented
- the JOHN PACE
(wife SARAH) of Surry Co., NC,
- the WILLIAM PACE
(wife SICELY WALKER) line,
- and the JESSE PACE line.
We have been advised by FTDNA
that Group 3a and Group 3b
share a common ancestor and that a rare 2-step change occurred that separates these two groups.
AT THIS POINT
WE HAVE NO WAY OF TELLING WHEN
and WITH WHICH PACE
this change occurred.
SO FEW NORTH CAROLINA PACE LINES
ARE REPRESENTED IN THE DNA STUDY.
We really need
Pace descendants with documented lines to the early RICHARD PACE of NC that descend from lines other than RICHARD PACE
(wife ELIZABETH CAIN)
to find participants from their lines, to be tested.
Until we have participants
from other documented lines we will not be able to determine when the split between Groups 3a and 3b occurred.
DNA testing still has the potential
to help many NC Pace descendants determine where they fit in the Pace family tree, especially if the split between Groups 3a and 3b can be determined.
Rebecca Christensen - 09/11/2005
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New postings
on Results and Donors pages of the DNA study
for kit 53888
There is a perfect match with 13827
both showing lineage to
RICHMOND PACE and possibly JESSE PACE
with a common mutation in marker 2.
Roy Johnson - 24/04/2006 - DNA coordinator
New results
have been posted on the DNA page for 57109
This submission goes back only to the donor's grandfather Cosby Alonzo Pace b. 1878 Cochran, GA, died prob. Brunswick, TN.
The results place this line clearly in group 3a, and should be helpful
in seeking further evidence. Perhaps the town names of Cochran, GA, and
Brunswick, TN will also help.
Roy Johnson - 06/05/2006 - DNA coordinator
Interesting new results posted
from donor 55605
showing that this person is in group 3a
but an interesting mutation in marker 23
Also, I made changes
in the explanation
of groups 3a and 3b.
I became confused between the three Richards mentioned in the Winifred Aycock Lane
letter (her father, grandfather, and great grandfather), and no one caught
it and yelled at me.
Please read the new explanations in the Results page
and see if they make sense.
SEE EXPLANATION
For those who may be unfamiliar
with the Lane letter:
We have hard evidence
that Richard of Jamestown had son George and grandson Richard, but here the
paper trail vanishes.
The only record we have of possible descendents was
written in 1791 by an old lady, Winifred Aycock Lane, relying on her memory
as told to her by her mother. She says her father was Richard and
Grandfather was Richard, Jr., and that they came from Virginia in a place
where "five counties meet".
No such place has been found, but it is assumed
(but not proven) that her great grandfather Richard was the aforementioned
grandson of Richard of Jamestown. She gives the names of her grandfather's
brothers. Those same names were found in North Carolina and assumed to be
the brothers.
DNA evidence supports that these Paces had a common ancestor within the
necessary time span, thus supporting (but not proving) that they are
brothers and could be descendents of Richard of Jamestown.
In addition, the lone UK Pace in this group, whose ancestry is from London, matches closely enough to lead to the conclusion that the common ancestor was from London,
as Richard of Jamestown was.
Roy Johnson
DNA coordinator
FTDNA has come up with an exciting new feature called FTDNATip that allows
closer comparison of two individuals with a percentage display of how far in the past their common ancestor might be.
One of the best applications of this is for us to determine the possibilities for the John of Middlesex group with GTP(of England) and DHP(of America); both having had 37 marker tests, with 25/25 matches on the first 25 and a couple of mismatches
in the 26-37 area, making them perfect specimens.
I ran the comparisons for them and got:
In comparing 37 markers, the probability that DHP and GTP shared a common ancestor within the last...
- 100 years is 26.85%
- 200 years is 65.86%
- 300 years is 87.35%
- 400 years is 95.88%
- 500 years is 98.76%
- 600 years is 99.65%.
I have not had time to apply this to any of the sub groups in the Richard
descendents. The tool is available only to project administrators at
present, but will soon be available to all, so that you can compare your
results with anyone else's that you choose.
Roy Johnson - 03/12/2004 - DNA administrator
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