Hi,
Your question:What exactly does the 1 step, 2 step, etc.. mean
Ok remember I'm still learning just like you are.
First lets say you have a males results from a test of his yDNA STR's lets
say it is a 37 marker test. OK?
and you compare these results (Called a haplotype) with the results of
another persons test.
each place tested is called a marker and has a marker name some are called
DYS and given a number. ok lets use DYS447. now your person's test has a
result of DYS447 14 and the person you are comparing to has a DYS447 15,
that would be one step difference from each other. Now lets say the first
man has DYS447 15 and DYS 390 12 and DYS391 10 and person number two has
DYS447 16 and DYS 390 10 and DYS391 9... DYS447 comparison would be one step
difference between the two, DYS 390 would be a two step difference, DYS391 a
one step difference, this equals a 4 step difference. no chance they are
related in the time frame of the use of surnames.
When you have tested enough people of the same surname your project manager
can try to figure out a haplotype of a common ancestor (note: yes this is a
guess to me, but not really.. scientifically it can be sort of be figured
out) So now you have this guesimated set of results you are using for a
common ancestor. this haplotype will be the one used to compare the real
person's test results to. the differences in the test results are refered to
as mutations because they have changed from the suspected common ancestor's
assigned results.
Because scientifically they can guesimate how often a mutation can change
they can esimate by the step differences between the marker results how
distant a common ancestor is.
In my case of Gilpins, we have a two step difference between two men same
surname tested at 37 markers. This gives about a 500 year guess to a common
ancestor. But we know for sure that they are related and now it is time to
prove it via paper genealogy.
Not discussing religion or evelution theroys.. The tree of man kind is sort
of like a tree with only one root. As you advance in years different
branches are formed on the tree. These branches are refered to as
Haplogroups. each haplogroup has changes from a different haplogroup.
The reason I'm going into this is that a person of a different haplogroup
can't really have the same results on a Haplotype (test results of a yDNA
STR test) but they can have near matches. Why because you are related but
related from your being in the same branch of the tree (common ancestor
before the use of surnames.. tens of thousands of years...) That is sort of
like the example of the 4 step difference example I used above.
Now did that answer you? Did it help or did I get to far off??
Nelda
Nelda's websites - Please visit
http://freepages.folklore.rootsweb.com/~bonsteinandgilpin/
Gilpin DNA Project member
----Original Message Follows----
From: Eve Black <sykoeve72143(a)yahoo.com>
What exactly does the 1 step, 2 step, etc.. mean
because on my Dad's dna we had more than one matches
in 1 step (and down) for Scotland and England, plus
some other countries). I am still learning about this
DNA and haven't been able to figure it all out yet.
Evelynmarie Carr Black
(descended from the Ferniehirst Kerr's)