Remembering
Ancestors
By Paul VanRaden
©2025
Topics:
Displaying ancestors in a pedigree
Ancestry
origins from pedigree
Ancestry
regions from DNA
Finding
DNA matches for relatives
Predicting
traits
Data
sources
Relationships,
inbreeding, and heterosis
Conclusions
References
Displaying ancestors in a pedigree
Most pedigree displays become very wide with many generations
and then leave much empty space at the left for the recent generations. Instead,
the display can list standard data fields such as birth date in one long column
together. After those fields, each generation can indent only a few spaces more
than the last, greatly reducing the width and giving a vertical pedigree with
one ancestor per row that can be easily emailed or printed on standard paper.
At USDA we wrote programs using those ideas to display ancestor information
from a database onto a screen beginning in 1993 and I used that strategy again
for my own pedigree below. Ideally this style could be programmed to provide
those same fields for any pedigree by pulling data from a database or an export
file, but I had to type this one by hand:
Ancestry origins from pedigree
People have wanted to know where their ancestors lived, how
long they lived, and stories about them for thousands of years since Biblical times.
Often, historians recorded only the all-male path from father to grandfather to
great grandfather, etc., or from father to son to grandson, etc. because family
names, property, and power were often inherited that way, such as with kings.
Many people even worship a father and a son but not a mother or a daughter. But
in this last century, females may own property, hold power, have equal rights
such as to vote, and deserve their history (herstory) told also. Hallelujah!
My nieces Hillary King and Andrea Sabaka found or stored
about 230 of my ancestors in a commercial database (ancestry.com) and added
many pictures and stories about their lives. Our American family had forgotten
much of this history, but our German cousins wrote a 100-page book about our
VanRaden ancestors and their families. Then I transferred the key fields into
the pedigree document above and used that to trace where our family’s DNA is from.
My sister Judy Winship thought of giving each generation a different color to
help see the connections. Humans will never get pedigrees as deep and accurate
as cattle because farmers gave cattle a 100-year head start and because cattle
generations take only 2-5 instead of 20-40 years.
Pedigree depth averages about 7 generations for me and my
sibs, 8 generations for our kids, and 9 for their kids. For 3 of my 4
grandparents, all 14 paths trace back to my 2nd or 3rd great
grandparents who immigrated to northwest IL from Germany around 1850. My
father’s ancestors were all from northwest Germany close to Netherlands and my
maternal grandmother’s were from southwest Germany near Stuttgart and one from
Frankfurt. Of my maternal grandfather’s ancestors, 94% trace to northeast U.S.
states (CT, MA, NH, RI) and only 6% go back to my 7th to 9th
great grandparent immigrants from England. In the 1700s, most New England colonists
were from England and my ancestors’ last names sound British, so my pedigree is
75% German, 2% British, and 23% probably British.
My initial genomic origins in 2025 were 63% western Europe
(45% northwest Germany, 11% Netherlands, 7% southern Germany), 34% southeast
England or northwest Europe, 2% north Wales or northwest England, and 1%
Czechia to the east of Germany. My 11% from Netherlands made sense since my
paternal ancestors lived just across the border and spoke the Low German (Plattdeutsch)
language common across northern Germany and northeast Netherlands.
My updated genomic origins in 2026 were from 14 instead of 6
regions because Ancestry.com added 156
smaller, more specific regions. For example, my 34% from “southeast England
or northwest Europe” is now assigned to 3 regions of England, 2 regions of
Germany, 4% from Switzerland, 3% from Belgium, 2% from France, and 1% from
northwest Italy. My 1% from Czechia is now 2% from the Western Carpathian Basin
which is an odd way to describe Hungary, Czech Republic, and Slovakia. Netherlands
dropped from 11% to 4% and northwest Germany rose from 45% to 54%, both more closely
matching our pedigree. I am no longer 100% European because according to their
math 3% of my DNA stopped in Quebec on its way to Illinois. Native Canadian is
in separate categories, so the Canadian DNA was likely from France but may match
cousins there instead of ancestors.
Daughter Angel and son-in-law Cesar both got initial and updated
DNA results that now include 24 and 25 ancestral regions. Angel’s initial
report had 62% DNA from Europe and 38% from Africa which are 63% and 37% after
the update. Initially she had <1% native American from Yucatan Peninsula but
they no longer report percentages <1%. Angel’s DNA from Africa was mostly
from Nigeria, Senegal, and Cameroon. Her percentages from each region in Europe
are about half of mine as expected plus 2% from western England and 1% from
Scotland / Ireland that I did not have. Those must have been from her mom
Cheryl’s ancestors, estimated to be 76% from Africa and 23% from Europe by
combining results for Angel and me and counting my Quebec DNA as French.
Cesar’s DNA had a wider mix of initial regions that totaled
39% from Europe, 49% from Africa, and 12% native American. His updated origin
percentages now include 21% from Canary Islands instead of 2% previously, but those
may be cousins rather than ancestors (like my Quebec DNA). I assumed his Canary
Island DNA is 16% from Europe and 5% from Africa to get his updated totals of 41%
Europe, 49% Africa, and 10% native America. By combining twice of Cesar’s
percentages minus his mom Jessica’s percentages, we also estimated that his dad
had 26% DNA from Europe, 66% from Africa, and 7% native American.
Cesar’s DNA from Europe was 22% from Spain and 2% from Portugal
as expected plus 1% from France. Initial estimates listed a few percent each
from Germany, Greece, and Azores that are now gone and make more sense. His DNA
from Africa was initially 35% western plus 9% central and 5% north African. New
regions are 11% from Benin, 6% Mali or Ivory Coast, 5% Senegal, 4% N Africa,
and 7 other regions with 4% or less. His native American DNA includes 6% from Puerto
Rico (Boriken) and 4% from Dominican Republic (Quisqueya) which both make sense
given his known ancestors from there. Much further back, native American DNA came
from Asia > 10,000 years ago and all other DNA traces back to Africa
>50,000 years ago.
My DNA is now 64% German and Dutch, 21% British, and 15% from
a little farther south and west instead of 75% German and 25% probably British
from our pedigree which lists the former hometown of each immigrant ancestor. That
seems more precise than a DNA test unless that immigrant had some earlier
ancestors from far away or the reported pedigree is not completely accurate.
But the DNA test more precisely estimated origins for the 23% of my pedigree
that ended in New England and did not trace back to immigrants. Just yesterday niece
Hillary found pedigree tracing back several hundred more years via royal
families in Europe but I did not update our pedigree with that yet.
Ancestry also graphs geographic regions of inheritance separately
by chromosome. Those make more sense in October 2026 than when first introduced
in March 2026. Previously, my whole chromosomes were always from 1 region or
another and no crossovers occurred. My Mom’s ancestors were about half from
England and half from Germany and then mixed for several generations in America
and my Dad’s ancestors and chromosomes were German as expected, but his
chromosomes 1, 11, 12, and 21 were shown as fully Dutch after 4 generations of chromosomes
mixing and recombining during meiosis. Previously Ancestry.com’s chat bot
replied that many regions are so similar that their Chromosome
Painter prefers keeping 1 color instead of switching back and forth many
times per chromosome. That is now fixed but a new issue is that with many more
regions I cannot quite tell which color is which.
At USDA we color-coded chromosomes in slide 8 of this 2010
presentation to correctly show actual chromosome recombination across 3
generations of genotyped ancestors for the first bull (named O-Style) that had
both parents and all 4 grandparents genotyped. Few humans yet have genotyped
grandparents, but some calves now have 8 generations fully genotyped.
Finding DNA matches for relatives
DNA testing companies can find close relatives also tested by
that same company, and 25% of my DNA matches my niece Hillary’s DNA, as
expected. My highest other matches were 5-7% with 2 sons of my paternal
grandmother’s sisters and with 1 granddaughter of my maternal grandfather’s
brother. She is my second cousin, but Ancestry suggested her as a 1st
cousin once removed or half first cousin. Some relatives share more or fewer
DNA segments than average, like not always getting 11 heads and 11 tails when flipping
a coin 22 times. Each parent has 2 sets of chromosomes, and at each location
you get their DNA from their mother or their father, but not both. Ancestry
correctly guessed which relatives were on my Dad’s side or my Mom’s side
because my great grandparents each had many descendants to help sort the DNA
into individual chromosomes, a mathematical process called phasing.
Ancestor discovery for cows is much more accurate because we
have DNA from 10 generations of ancestor bulls and very complete and accurate
pedigrees for all bulls across the whole world. Future generations of humans
will have more of their ancestors’ DNA already analyzed. That will simplify the
process of connecting relatives because each next generation can just confirm
their direct relationship to their ancestors’ DNA instead of indirect
relationships to cousins’ DNA. Many dairy farmers across the world now trust
our programs to create pedigrees for their cows and calves using the DNA
matching system that my coworkers and I developed at USDA. Parent matching is
very easy, and already > 2 million unknown grandparents
and great grandparents were discovered by DNA and automatically added to
the global cow pedigree file. My previous job at USDA also included estimating
genomic origins for millions of cows. For cows or for dogs, scientists use DNA
to check breeds
of origin instead of places of origin.
Ancestry.com also predicted many traits as yes/no or high/low
and a few traits had high/average/low. For predictions of my traits, 28 seemed
correct but 19 seemed wrong. That may not be very accurate if one of the two
categories is much more frequent than the other. For example, if 15%
of people have freckles you could get 85% correct predictions by always
guessing no freckles with no data. Some Ancestry traits use markers known from
literature to have large effects but most traits use survey replies from their
DNA customers. Strangely, they did not predict height, which is highly
heritable and was the first trait that human geneticists studied in detail in 2010.
That study used almost the same genomic methods we developed at USDA and used for
predicting cow stature since 2008.
Predictions for 50 cattle traits each come with percent
reliability estimating how accurate they are expressed as a squared
correlation. The trait predictions are expressed using 2 or 3 decimal digits
instead of binary yes/no. Genetic effects can be estimated very precisely even
if the observed traits are predicted less well due to low heritability. Farmers
use the predicted traits to directly manage the current generation or to select
the next generation, and most cattle traits have known economic values.
Thus, farmers can easily profit from cattle DNA predictions available since
2008 and pedigree predictions since 1926. Human DNA tests are mostly for
entertainment. Trait predictions began much earlier at 23andMe, off and on since 2007
due to changes in regulations, than at Ancestry.com since 2018.
The technology to read DNA is almost
the same across many different species. For humans, several different companies
collect DNA samples and store pedigree data. Ancestry.com has sold over
28 million DNA tests as of 2025 and 23andMe sold 14 million DNA tests
as of 2024. The largest cattle DNA database begun by USDA and managed by the
Council on Dairy Cattle Breeding has over 11 million DNA tests as of
2025.
For humans, competing companies likely do not yet share
pedigree data. Even within Ancestry.com, their German database had pedigrees
for several older ancestors that were not in the American database. For dairy cattle
since 1995, Interbull in Sweden receives full pedigrees from about 25 countries
for all commercially available dairy bulls. Interbull then sends to each
country a complete file of combined and edited pedigrees from all the world’s
bulls for several different breeds. Dairy cattle breeders want to see the full
global pedigrees because most Holstein bulls have foreign
fathers or grandfathers. Cattle are not forced to stay within country
borders. Cows are one big, happy family across the whole world. Hallelujah!
Knowing names and locations of ancestors is not as
interesting as learning stories or seeing pictures from their lives. For
example, our German cousins documented the lives of our VanRaden ancestors that
we American descendants had forgotten:
Relationships, inbreeding, and heterosis
Inbreeding coefficients are very important in livestock
breeding because progeny may be less healthy if parents are too related. Most
humans are much less inbred than most livestock. I did not get either DNA or
pedigree estimates of inbreeding from Ancestry, but my pedigree inbreeding may
be 0 because I did not notice the same names among my maternal and paternal
ancestors. We could imagine finding 5 or 10 more generations of ancestry and then
my inbreeding coefficient might be a tiny bit above 0 but nothing to worry
about.
The pedigree methods
that quantify how inbred or how related any 2 individuals are to each other
were published in 1922 by geneticist Sewall Wright from the same USDA research
center where I worked. His parents were cousins which likely got him interested
in the topic. His example in paper was a cow pedigree, but his methods are now used
for all species. Then in 2008 I published DNA-based methods to
estimate how inbred and how related cows are to each other. Those methods are
now used for DNA predictions of traits for countless other species, but the DNA
relationships from most companies now use haplotypes instead of genotypes after
statistically separating the 2 sets of chromosomes into maternal vs. paternal
DNA.
People in the Americas might be a little less inbred than people
within Europe, Asia, or Africa whose ancestors all lived in the same nation or
small region of it. DNA can quantify those differences. For example, my DNA may
be a little more diverse than my father’s because 100% of his DNA came from
northwest Germany whereas I have 75% German and 25% British ancestors. My
mother may have lower DNA inbreeding than both of us because her father had
British DNA and her mother German DNA with even less chance of any common
ancestors. My daughter has no inbreeding and some positive heterosis with a
mixture of European and African DNA. Latin
Americans often have mixes of native American, European, and African DNA.
The term heterosis describes effects that cannot be traced by pedigrees when
the 2 parents have DNA from different populations that were separate for many
generations. Inbreeding
and heterosis are similar topics.
Genealogy was a hobby for millions of
people but was a big business for livestock breeders for more than a hundred
years after breeds were defined and trait data collection began. Large
databases allowed farmers and breeding companies to predict and to select for
traits they wanted livestock to have. Knowing about your pedigree and your DNA is
still mostly a hobby and a curiosity for humans but is beginning to be useful
for separating genetic from environmental causes in medical treatment.
Future generations may find services offered by genealogy companies more useful
or even get better DNA
than we got. Our genes have big effects on many of our traits, and better understanding
our DNA could improve everybody’s lives in the future.
References
Sewall
Wright, 1922. Coefficients of
inbreeding and relationship.
Discovering
ancestors and connecting relatives in large genomic databases - ScienceDirect
Fast
two-stage phasing of large-scale sequence data: The American Journal of Human
Genetics
Genomic
predictions for crossbred dairy cattle - Journal of Dairy Science
Efficient methods to compute
genomic predictions - PubMed
Invited
Review: Reliability of genomic predictions for North American Holstein bulls -
ScienceDirect
How
Common Are Freckles? Global Statistics
Common SNPs explain a large
proportion of the heritability for human height | Nature Genetics
Timeline for 23andMe
DNA testing
Countries
Where AncestryDNA® is Available
Deep
Dive: AncestryDNA 2026 Regions Update
Ancestry
Launches a New Take on Genetic Traits
How
We Develop Traits - Ancestry DNA
TraitsPredictionWhitePaper_042024
Return to Genes for the Next
Generation