Darnall Group DF02
Darnall SNP Tree, R1b-BY125922
- Think of the Y chromosome as a stream that passes through every
generation of males, branching into different forks with each son. Much
like debris swept along in a river, the end point (the tester) is an archive
of all the mutations that proceeded him, just as a small cove collects all
that was swept down the river.
- A SNP mutation is briefly described in this micro
lesson.
- Each alphanumeric designation is rather arbitrarily assigned but does
represent a SNP mutation found in the tester's Y chromosome. And each
SNP arose at the birth of a specific ancestor, most of whom we will
never be identified by name.
- The SNPs are arranged by groups, known as haplogroups. A haplogroup is
defined by multiple testers who share the same SNPs with one another, much like
siblings sharing the same parent, or cousins who share the same
grandparent. Genetic similarity dovetails with a genealogical relationship;
the more similar the genetics, the closer the relationship.
- And haplogroups are arranged in a timeline, the older haplogroups at the
top, the more recently emerged at the bottom of the tree. The continue to
climb up three tree and into the past. The oldest known SNPs are about
330,000 years old. The tester can research his SNP tree and see the
numerous branches in his account at FTDNA. This is just a small sliver.
- The SNPs in the light blue
box are those that have been found (to date) to belong only to the
tester. There are matches out there, they just haven't yet been tested. If
a fifth couisin, for example, were to test, he would match the vast majority
of the present novel (or private) SNPs.
- Although the emergence of SNPs is random and will vary from one lineage
to the next, it can be reasonably expected that they occur on the average of
one per every four generations. The 26 private SNPs listed here, then,
might cover about a hundred generations, or about three thousand years.
Clearly, there a long way to go before drawing a rather detailed SNP
lineage. And, certainly, some of the novel SNPs are well within the
genealigical timeframe. In other words, one day some of them might
resaonably be identified by name, date, and place.
- The following page, also maintained by myself, is a moderate example as
to how detailed a SNP tree can become — and it's even hindered by a
lack of a sufficient number of advanced testing: R1a-YP4248 Subclade Project.
Every tester's lineage can be extracted and arranged in the manner at
left.
Y-111 STR Results
There are four testers in Group DF02, two of whom have tested for at
least 111 STRs at FTDNA. There is a six-marker difference between them
(known as genetic distance or GD), but that's reasonable. But taking these
and the SNP results together, we have a fairly good genetic representation
for this lineage. However, we need more SNP testing in order to home in on
Morgan's exact Y-DNA print.
Additional Information
FTDNA Home of
the Darnall / Darnell FTDNA Project
Family Trees
Associated with the Darnall Project
1920 Family Profile For Richard Bennett Darnall (1877-1957)