Introduction to using DNA with genealogical records to grow your family tree

1. GENETIC GENEALOGY
USING DNA TO GROW YOUR FAMILY TREE

2. What is genetic genealogy?
Genetic genealogy is the use of DNA testing in
combination with traditional genealogical and
historical records. Genetic genealogy involves the use
of genealogical DNA testing together with
documentary evidence to infer the relationship
between individuals.

3. DNA Defined:
DNA, or deoxyribonucleic acid, is the genetic
code, or blueprint, that plays a big part in
defining who you are.
Every cell in your body contains a copy of your DNA,
which is a microscopic set of instructions that
determine what you look like and other personal
traits. While most of that code is the same from one
person to the next, there are specific variations that
make you unique.

4. The length of a piece of DNA is measured
in centimorgans. The total length of all your
chromosomes combined is around 7400
cM.
Since a person inherits half of their DNA
from each parent, you share about 3700
cM with each parent. The exact number for
each parent/child relationship can vary
slightly, but not by a lot.
Full siblings tend to share around 3500
centimorgans
A centimorgan is a unit of genetic
measurement. It's what experts use to describe
how much DNA and the length of specific
segments of DNA you share with your relatives.
These shared segments are divided up
into centimorgans. The
more centimorgans you share with someone,
the more closely you are related.

5. A haplogroup is a genetic
population group of people who
share a common ancestor on
the patriline (Y-DNA) or the matriline
(mtDNA). Haplogroups are assigned
letters of the alphabet, and
refinements consist of additional
number and letter combinations.
At its essence, a haplogroup is an
ancestral clan. Some clans are the
Vikings, Native Americans (all tribes),
Celts, Aboriginal Australians, and
other such groups. Your haplogroup
tells you where your ancestors came
from deep back in time.
My patriline haplogroup is R-M269.
My matriline haplogroup is L1c2a1b

6. NPE
Not Parent Expect
Non-Paternity Event
This occurs when your biological
is not the parent you know.

7. TYPES OF DNA TESTS FOR GENEALOGY
AUTOSOMAL (admixture or atDNA)
Y-CHROMOSOME DNA TEST (yDNA)
MITOCHONDRIAL (mtDNA)
X-CHROMOSOME (xDNA)

8. AUTOSOMAL DNA is inherited through the 22 pairs of
autosomal chromosomes, not the x or y determining
chromosomes.
It can go back to 5-7 generations or about 200 years.
Autosomal DNA tests can tell you a lot about your ancestry
and your chances of getting certain conditions with a pretty
high level of accuracy. This is done by finding specific
variations in your genes and putting them in groups with
other DNA samples that have similar variations.
Those who share the same ancestors will have similar
autosomal gene sequences. This means that these DNA
tests can help trace your DNA and the DNA of those
distantly related to you back to where those genes first
came from.

10. Y-DNA is the chromosome which determines if you are a male or not .
It is passed down from father to son. It is good to use to determine male paternity.
It verifies male lineage. Since women don’t have y-chromosomes, they can’t take y-DNA tests
(though their brother, father, paternal uncle, or paternal grandfather could).
Y-chromosome testing uncovers a male’s y-chromosome haplogroup, the ancient group of people
from whom one’s patrilineage descends. Because only one’s male-line direct ancestors are traced
by y-DNA testing, no females (nor their male ancestors) from whom a male descends are
encapsulated in the results.
So, a male can trace his lineage through his father, grandfather,
great-grandfather, etc.

11. You receive on x-chromosome from your mother and one from your father.

13. MITOCHONDRIAL DNA (mtDNA) Mitochondrial DNA tests trace people’s matrilineal
(mother-line) ancestry through their mitochondria, which are passed from mothers to
their children. Since everyone has mitochondria, both males and females can take
mtDNA tests.
Mitochondrial DNA testing uncovers a one’s mtDNA haplogroup, the ancient group of
people from whom one’s matrilineage descends. Because mitochondria is passed on
only by women, no men (nor their ancestors) from whom one descends are
encapsulated in the results.

14. SIBLINGS EACH RECEIVE A HALF OF THEIR DNA
FROM EACH PARENT.
AS DNA IS PASSED DOWN THROUGH THE
GENERATIONS SOME DNA IS LOST

16. COUSINS COMMON ANCESTOR POSSIBILITIES
1st Grandparent 4
2nd Great-grandparent 8
3rd 2nd Great-grandparent 16
4th 3rd Great-grandparent 32
5th 4th Great-grandparent 64
6th 5th Great-grandparent 128
7th 6th Great-grandparent 256
8th 7th Great-grandparent 512
9th 8th Great-grandparent 1024
10th 9th Great-grandparent 2048

17. MAJOR TESTING COMPANIES
WWW.ANCESTRY.COM
WWW.23ANDME.COM
WWW.FAMILYTREEDNA.COM
WWW.LIVINGDNA.COM
WWW.MYHERITAGE.COM

19. The Leeds Method is a simple and colorful way to
organize your DNA matches using color-coded
clusters.
The goal of the Leeds method is to help you quickly
identify groups of people in your match list who are likely
to share a common ancestor with each other. Grouping
your matches often makes it easier to identify a common
ancestor.
To use the Leeds Method, create a list of your 2nd and 3rd
cousin matches. In general, these are those in your match
list that share less than 400 cM of DNA but more than 90
cM. Create this list in a spreadsheet program like Excel.
The Leeds Method

21. To do this on Ancestry.com, click on
the cousin’s name and then click on
“Shared Matches”.
2. Using the Shared Matches tool, find
the other matches in your match list that
share DNA with that first one. Fill in the
cell next to their names with the same
color as the first one.

22. 3. Find the next person on your match list that
wasn’t colored with the first color. Assign that
match a different color and fill the cell in the
second column with the new color.

23. 4. Using the Shared Matches tool again, fill the cell in the
second column by those matches that share DNA with this
second match.

24. 5. Look down your match list and find the first
person that doesn’t have either of the cells
colored by it. Pick a third color and fill in the cell
in the third column by that match.

25. 6. Use the Shared Matches tool to find
the other DNA matches in your list who
share DNA with that match. Color the
cells in the third column for those who
share DNA with this match.

26. 7. Look for any matches that don’t belong to
the three groups you have already colored in.
Assign them a new color.

27. 8. Using the shared matches tool again, look for any
matches that share DNA with this match and fill in the
color in the fourth column.
9. Keep repeating this pattern until all of the matches in
your list have at least one color assigned to them.
Keep in mind that some of your DNA matches may share
DNA with more than one color group. This is ok: just color
multiple cells with the corresponding colors. This is called
overlap.
These colorful groups now show you the different genetic
networks. Theoretically, each of the four colors should
correspond to one of your four grandparents.

34. 7. Enter the required information. The left image is for FTDNA.
The right for Ancestry.com.

35. THERE ARE
FACEBOOK
GROUPS THAT
WILL HELP
YOU
UNDERSTAND
YOUR DNA
RESULTS.