Hi Paul G,

I'm sorry about that.  I guess in my rush I forgot to mark the email so I
could go back later and answer in more detail.  Thanks for the reminder!

There are different types of DNA testing.  We've all heard about criminals
and their DNA being run through CODIS (COmbined DNA Index System) - at
least in America.  These are unique, identifying markers where scientists
can say it was a 1 in a trillion chance.  We don't use these for
genealogy.  We want to know what unites us and makes us alike, not unique.

There are also tests on the market for medical DNA testing.  You can find
out if you are more at risk for certain diseases.  Family Tree DNA (FTDNA)
is not involved in medical DNA testing.

The 3 tests on the market for genealogy are Y-DNA, mtDNA (mitochondrial
DNA), and autosomal DNA (atDNA - FTDNA calls it their Family Finder).  Not
all companies that use DNA for genealogy offer all 3 types of testing.
FTDNA does.  They've been in the business of DNA for genealogy exclusively
since 2000.  They have a very reputable advisory board.  They have the
largest database.  Those are some of the reasons why the Azores DNA project
was set up with FTDNA.  Now for the 3 types of testing.

1) Y-DNA:  The Y chromosome is part of the 23rd pair, or the sex
chromosome.  It is what makes you a man and me a woman (the other 22 pairs
are autosomes and I'll discuss them in # 3 below).  For you to be a man,
your 23rd pair is an XY.  I'm an XX, being female.  What this means is that
you got the X from your mom and the Y from your dad.  You dad, being male,
was also XY.  He got the X from his mom and the Y from his dad.  Your
grandfather, being male, was also XY.  He got the X from his mom and the Y
from his dad.  So the Y chromosome follows the top of your pedigree chart,
or a strict, all-male line:  Your father's father's father's father all the
way back in time. Since I am a female and have no Y, I had to find a male
in my line to take the test (my dad).  Now, if you want to focus strictly
on 1 line, this is the DNA test to take.  (And for those who want to know
why they don't test the X of the XY pair...the X did come from mom, who was
XX.  Which X did your mom give you?  Her mom's or her dad's?  The
scientists can't tell so we don't use it for genealogy testing).

2) mtDNA (mitochondrial DNA): The mitochondria is the powerhouse of the
cell and it houses mtDNA in its nucleus.  There's a lot of of and it is
very hardy and can withstand time and deterioration.  A mother (female)
passes it down to her offspring.  So either men or women can test their
mtDNA. It traces the mother's mother's mother's line, or the bottom of you
pedigree chart.  All women, all the way back in time.  The strict,
all-female line.  However, because of its hardiness, it rarely mutates.
It's much harder to use it to for genealogical purposes.  It's best use
would be if you and I were in the same freguesia and we see our 5great
grandmas (who are our mother's mother's mother's mother) being godmothers
to each other's kids and we really think that they are sisters, but the
records run out.  If we both did a DNA test and had the same mutations,
then we could be sure.  But just to do it and hope for a match without a
location or theory is slim.  However, the 1st DNA match made in the Azores
DNA project was through mtDNA.  Both participants (a man in Brasil and a
woman in California) had a rare mutation and were in adjacent freguesias.
Research later proved they were related.

3) atDNA (autosomal DNA/Family Finder):  This involves the other 22 pairs
of autosomal DNA.  You got half your DNA from mom and half from dad.  Your
parents got half from their parents; therefore, you have 25% of your
grandparents DNA, 12.5% of your greats DNA, 6.25% of your 2 greats, 3.125%
of your 3 greats, etc.  Because this is looking a a cross-section of DNA
that recombines, it covers all of your pedigree chart, back approximately
200 years (or 200 years from the person taking the test.  My dad, born in
1934, has DNA matches that I don't have because his DNA is taking him back
to the early half of the 1700s whereas my DNA only goes back to the
mid-1700s).  Now, if you and I share the same 3 great, we should have about
3% of their DNA in our genes.  However, we don't have the SAME 3%, but
different fragments of it.  And if "Fred" shared the same 3 great, he may
not even show up in my matches, but in yours because he has a different
fragment that matches one of yours, but not one of mine.  So even though
this uses our complete pedigree chart back about 200 years, we need to have
MOST of our lines back, and we need to have it uploaded to our FTDNA page
so we can look for the common ancestor.  Or if we are not back that far, at
least the freguesia so we can have a clue.  We may not know initially which
3 great we have in common, but with a little detective work, a few emails,
and a lot of patience, we can figure it out.

So, do you want to focus on one line at a time? (Your father's father's
father's or your mother's mother's mothers)? You will probably wait a few
years for a significant genealogy DNA match (especially if your Y is
Portuguese).  Or do you want a cross-section or overview of your DNA?  If
you are 100% Portuguese, you will have approximately 2-4 pages of matches
(at 10 people per page).  If you are a mixture, you will have more pages of
matches (my dad is half Portuguese and is up to 19 pages of matches now.
About 2 to 4 of them are Portuguese and the remaining are British Isles
type surnames from his mom's tree). If you go for Family Finder, it will
take time to wade through the matches and figure out exactly how you match
these people.

Hope this helps.  If you have any further questions, let me know.
Cheri Mello
Listowner, Azores-Gen
Researching: Vila Franca, Ponta Garca, Ribeira Quente, Ribeira das Tainhas,
Achada

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