Are you wondering can your DNA results be incorrect? Well,
today we're going to answer that question. Howdy and
welcome to Family's Fanatics where we love helping you climb
your tree and have fun along the way. If you're new to
genetic genealogy, you probably have tons of questions. Be sure
to check out the link in the description below for our free
guide to the five most common questions we get about DNA. We
all have DNA. In fact, ninety-nine point nine percent
of our DNA is the same. So, really simply if you want to go
by that, you don't even have to be tested and you already know
what 99. 9% of your DNA is which in most cases, that's a
perfect A, if not an A plus but I don't think that's what you
were thinking. You may have heard some people say, oh, I
got my DNA tested but the results are so wrong. It's
nothing like what I am or hey, if I get this tested, which
company is the most accurate? Both of those questions tend to
think your DNA results can be incorrect but I think what is
the problem is most people who are asking that question are
asking the wrong question. Let's look at two ways that our
DNA results are correct or incorrect. First way is the
actual raw data. Our DNA is made up of three billion
letters or really three billion ACTs or It's not all the
letters of the alphabet, just those four. So, in 3 billion
places, we have an A, a T, a C, or a G and when we're doing a
DNA test, what they're looking at is they're looking at about
500, 000 of those places. So, they have five hundred 000
chances to get something wrong. Is something going to go wrong
there? Yeah. Does it happen a lot? No. Not at all. In fact,
I've compared my DNA that's been tested between multiple
different companies and from just a simple processing error.
In other words, let's say three of the companies say that I'm
an A in this location and a fourth company says I'm a C in
this location. Just by looking at those, what I found is that
less than half a percent of any time that I'm looking at the
same location, the DNA testing companies are going to get it
wrong. Less than half a percent. So, that's still
ninety-nine point five percent correct on what they're testing
and remember, they already know what the other 99. 9% is. So,
you're looking at ninety-nine point nine nine nine five
percent, that's pretty accurate. So, the raw data by
and large is not incorrect. Usually, if there is a major
error when you're testing, either there's not enough DNA
or something with the sample goes wrong in the processing.
What the company will do is send you an email and tell you
that hey we had a problem with the processing we'd like you to
take another test so that there's another sample when you
do that then they're going to process that sample now the
reason why they can be so accurate is because they're
actually running lots of tests over and over so they're not
just looking at a letter once they're not just looking at
that location once they're looking at that location
several times and analyzing it time and if it's coming up with
the same letter every time then they're confident to say that
it is that letter in some cases they may have it where
sometimes it's coming up this letter other times it's coming
up with this other letter and they'll say that okay this is a
no call in other words we're not going to tell you what that
letter is because for whatever reason we just can't get that
information right the amount of no calls that you have in your
DNA is also less than that. 5 percent just not that many of
them. So, overall, when you get your results, that raw data,
99% of it is going to be the exact same every single time
you test because that's really the round the accuracy of these
tests. So, if you believe that 99% is not good enough, then
yes, you can say that your DNA test is incorrect. However, I'm
of the opinion that a 99% is more than an A I'm going to say
that it is correct. Now, the next part of DNA testing is
really where people are talking about when they're asking this
question and that has to do with ethnicity results. It has
to do with your matches and it has to do with any medical
information. So, three different areas that companies
may tell you some information about. So, let's look at each
one of those. First off, with your ethnicity results. One
thing to always remember is that the companies will tell
you these are ethnicity estimates. It is not
definitive. And what these estimates indicate is where
some of your ancestry may have been. It is not a guarantee
that your ancestry is from there. Now most of the
ethnicity results are great at the continental level and even
at some of the sub regional levels. There's certain
populations like Ashkenazi Jews who have had a community that
is separate from most of the others and so their DNA has
remained very separate from the communities around them and so
they can actually pull out what DNA might be Ashkenazi Jewish
on the other hand most of the companies will also drill down
to even smaller and smaller levels. One of the problems
with this is that there has been a lot of immigration and
moving over the last centuries. And so just because today's
people and maybe the People of an area have lived there for a
couple of hundred years doesn't mean that they lived there 300
years ago or 400 years ago or 500 years ago for that matter.
DNA is great for ethnicity at the continental level. Yes,
that is correct but it's really uncertain the smaller down you
get and so in some places when you're talking about a certain
county or a certain town, I wouldn't I wouldn't change my
birth certificate or anything like that. Um I wouldn't change
who I think I am because of that. Next is the match data.
The people that you match with. This also has a yeah there's
some and then there's some not. So let's talk about the sum.
Some of these are definite matches. People that you share
DNA with. Particularly your close relatives. So second
cousins, first cousins, brothers, sisters, half
siblings, anything like that you share DNA with for sure.
And therefore, you are going to show up on their match list and
they're going to show up on your match list. Now, some
people think that they're incorrect because some of these
known second cousins or first cousins don't show up, it
probably means that there was something in the family that
happened and there's a father or mother that's not really the
father or the mother and that's who you thought you were
related through but because they're not showing up as being
related to you, you're not really related and that's just
at the close relationship level. Now, once you get to
third cousins, you don't share DNA with all of them and the
further out you go, the less of that group of people you share
DNA with. So, for instance, third cousins, you share about
90% you share DNA with 90% of your third cousins but once you
get to fifth sixth cousins, it's 5%, not that much at all.
So, only 5% of your six cousins do you share DNA with which
means there's a lot of people that you're related to you
don't share any DNA with. The other thing that you will find
on your match list is you're going to find there's some
people that you just can't figure out a connection to. Now
these people usually share you know ten or 12 maybe fifteen.
I've seen as much as 20, 2five centimorgans which still is not
a lot but there's a percentage of these people that you don't
have a genealogical relationship with. In other
words you're not really related within the last 10 years. Yeah
you might be related 1000 or last ten generations, not 10
years, last ten generations. You might be related a thousand
years ago but not in any time that you're going to be able to
figure out from a genealogical perspective. These are false
matches. Now, these smaller amount of DNA that you share
with somebody, the greater likelihood that they are a
false match. So, for instance, at around seven centimorgans,
50% of your matches are false matches. In other words, you're
not going to be able to find any way that you're related
because it is just too far back. As you down to something
like three centimorgans it's more than 90% of your matches
are false matches whereas up to about 13 or 14 centimorgans
around there you're only looking at about 2% of your
matches are false matches now like I said I have seen some
instances where 20to 25 centimorgans there was a false
match but I'm you know still curious about that because it
might just be a line that they haven't figured out everything
with so When you're looking at your match data, close
relatives are correct. Distant relatives, there's some
percentage of them that are incorrect. They're false
matches and you're just not going to know that from your
own single test. You actually have to have lots of different
people in your close relative family to determine whether or
not that's a false match or not. So, the third area then is
medical or health information. There's, you know, as with all
the DNA. It's like there's two parts to everything or three
parts. In this case, we have certain things that are 100%
dependent on our DNA. For instance, our hair color, our
eye color. What our blood type is, A, B, or O. All these
things are dependent sometimes on a single gene of DNA or they
are dependent on a few of these genes, few of these places that
have differences but these are dictated by your DNA. On the
other hand, there are lots of things like your susceptibility
to certain kinds of cancer or ability to to taste different
things that have a DNA component but there's also some
other things that are going on that scientist have just not
figured out completely or they're completely outside of
DNA. For instance, environmental factors. In this
case, just because you have a propensity to let's say obesity
or propensity to breast cancer doesn't mean that you're 100%
going to get it. Likewise just because you don't have this
propensity or you don't have the genes for this also doesn't
mean you're not going to get any of these diseases or
conditions. Because there's an interaction with all these
different things going on really the best that scientist
can do is tell you a percentage of how much your genetics
affects it. It doesn't tell you whether you're going to have it
necessarily. So again, when we're talking about medical and
health information, some things, yes, whatever your DNA
reports is correct and for other things, it might be
incorrect but it's not because of any kind of processing, it's
just because there's so many different factors that are
going on. So, in the end, when we're talking about whether or
not our DNA test is correct, we need to understand what aspect
of it we're talking about. Now, if you'd like to learn more
about redheads, you can watch this video right here but if
you want to learn more about something else related to DNA,
then check out this other video down below.