The
DNA dilemma
The current interest in the developments of DNA research
has generated an interest in using the techniques for family
history research. On the surface most of the work undertaken
by forensic scientists seems easily transferable to family
history. While this may be the case, the cost is well beyond
the reach of most private researchers and even if one was
able to find the $1500 per test, the tests available for
this fee are at best, mere guidelines and at worst useless!
You may be asking the obvious question—why are
such tests considered appropriate by forensics and the
courts
in identification? The standard test used in South Australia
involves the matching of ten points in the DNA map. (I
intend to avoid terminology in this article whenever possible.)
Matching ten points is quite sufficient when you are trying
to identify a person and their relationship to another
person or to their DNA fingerprint left on their tooth
or hair brush. Get just one point wrong and you can be
reasonably certain you do not have a match regarding parentage
and absolutely certain if you are identifying a person
from a trace of DNA! On the other hand in family history
we have quite a differing set of circumstances. Essentially
family history is a search scenario. On the one hand we
are hunting for distant living relatives who may hold knowledge
and/or artefacts of our common ancestor, or we are searching
for that elusive ancestor via a paper trail using records
generated by our ancestor and/or the various bureaucracies
in their time.
DNA is a good tool for identifying close relationships
or individuals and unfortunately in family history unless
we are adopted, we usually know our close relatives. Most
authorities on the subject dismiss the ten-point matching
for family historians embarking on the search for distant
relatives as useless. If we could test all the men in one
country today, we would find many matches using low-resolution
tests. Many more points or markers are required because
we cannot dismiss non-matching points in this aspect of
genetics. This is because over time we can expect mutations
in the DNA map to occur so that we cannot expect exact
matches and there could be even less matches as we go back
in time. Current thinking is that the twenty-four point
matching process known as a medium resolution test is probably
inadequate and that thirty-seven to forty-three marker
(high resolution) tests which are extremely expensive,
are far more reliable.
The matter of mutation has to be one of the most difficult
concepts to translate into reading the results of a test
for family history research. When is a match a match? Just
how similar do DNA maps (DNA haplotypes) have to be before
we can say with some surety that they are of some interest?
Scientists have given each marker they test, a numerical
value (allele value) and most mutations involve a single
step and to a lesser extent, two step change in the value.
The problem is that mutating is not predicable and we cannot
even be certain how often the changes may occur over a
long period of time. Clearly the more markers we examine,
the more likely we will improve the chance of a statistical
match. Some markers seem to be prone to mutation. Fortunately
some DNA maps are quite rare and if you are fortunate to
have such a result you may be able to expect a greater
level of success.
Another factor that must be taken into account is the limitation
the various DNA tests place on the results. Basically the
tests fall into just three categories. Some understanding
of these tests is necessary to understand the strengths
and limitations of DNA tests for family historians. Nuclear
DNA is the generalised testing used by forensic scientists
to identify individuals. In the main it has a limited application
in family history unless the task is to determine a relationship
such as may occur in determining an adoptee’s natural
siblings. Since both parents contribute half their chromosomes
to their children, it follows that unless you can test
each generation in turn, there is no way of progressing
this process beyond very close members of the family. Geneticists
need to focus on the material known to pass on down the
generations and this means the male Y-chromosome. Y-chromosome
tests track the male line, that is the surname line, and
naturally are only available to men. Mitochondrial DNA
tests can track the female line as the mother provides
her offspring with all their mitochondrial material. Unfortunately
Mitochondrial DNA mutates quite rapidly and while this
makes it useful for pinpointing changes and migrations
of peoples, it has little use to the specificity required
of the family historian.
The match of two men in a test is invalidated if they do
not share surnames. This important rule is often overlooked.
To understand why this is so, we need to have a basic understanding
of how surnames were adopted and how they spread and the
DNA map. Nowhere was the adoption of an add-on name a single
event but rather it took place over generations. If we
just look at England, the idea of a surname came from the
upper class of the Norman conquerors whereby they identified
their place origins as an add-on to their name. Theories
abound to explain why surnames were adopted, became hereditary
and why women adopted their husband’s names on marriage
and even more theories attempt to explain the origins of
surnames. The hard fact is that by the time of the 1377–1381
poll tax just about every taxpayer in England had a surname.
Into this mix we need to add the fact that spelling was
not standardised in England until the advent of the modern
era of bureaucratic centralised government in the early
part of the nineteenth century and the impact of the advent
of civil registration and the general accounting of the
population along with the movement towards the education
of the masses.
Unfortunately some people have a common surname and that
will not help in using DNA in the search process. Luckily
rare surnames are more common than common surnames but
they hardly help the reader endowed with a common surname!
Researchers suggest that about seventy percent of all surnames
in England are uncommon. Thus it is the combination of
the surname and the DNA map that is the key. Even then,
we cannot be certain of a match although if research suggests
that the persons undertaking the test have a distant ancestor
in the same location, the evidence of a relationship becomes
just that much stronger. This is because evidence is now
suggesting that many of the uncommon surnames originated
in a specific location. The now well-known Sykes name research
published in 2000 led to this understanding and indeed
this work has singularly encouraged many family historians
to consider DNA testing to progress their family history
research. A syke is a local term for a boundary ditch in
Yorkshire. Prior to this research it was argued that the
surname Sykes had been adopted by many different and unrelated
men in England resulting in about 10,000 people bearing
the name in England today. DNA maps of Sykes have suggested
that there may have in fact been just one original man
who took the name, Sykes.
Looking at the rare surname Jaunay, which has less than
300 entries in the telephone directories of Australasia,
Britain, France and North America, we could use Y-chromosome
tests to ascertain if these people have a likely common
ancestor. At this stage these people make up thirty-four
families and no linkages have been determined. However,
even if all parties consented, which seems most unlikely
as many do not even answer correspondence, the result will
only determine whether they have a common ancestry and
nothing more. The work will not name this unknown person,
nor will it be certain just when in time and where this
man lived! To date no Jaunay researcher has been able to
bridge the gap between the Jaunays living post 1750 and
those living before 1700. No amount of DNA testing can
bridge that gap in the paper trail! Frankly the Jaunays
would probably get better value for their money paying
researchers to trawl the records held in the Archives
Nationales Paris in an attempt to bridge that gap in the record! Now
in another scenario, if one family had managed to jump
a gap in the records, then using DNA to determine relationship
with that successful family would enable the other families
with that surname to jump the gap too without the need
to find the documentary evidence.
Since family historians cannot easily exhume the bodies
of their ancestors, even if they could locate them, and
conduct DNA tests to confirm their relationship, what use
is DNA testing? Essentially the best chance of a result
lies with the location of distant living relatives who
may hold knowledge of interest to us. This is where the
immediate future of genealogy and genetics lies. Locating
distant living cousins can be the most rewarding aspect
of family history research but many become preoccupied
with the paper trail. In fact these distant relatives may
prove to be the custodians of your family history. Currently
there are nearly 1500 surnames projects worldwide. The
goal here is to locate and identify extended family often
using Soundex to overcome surname variants. These surname
studies require a large number of male participants to
create a DNA map for a particular surname. One day these
signatures may become numerous enough especially as the
testing costs lessen, to be of some use. Of the 1500 or
so surname projects, the Graves family (a maternal aunt
of the author married a Graves) is one of a handful of
these projects that have already tested more than a hundred
men and developed a workable DNA signature. Others known
to the author include, Bassett, Bolling, Donald, Hill,
Rose, Walker and Wells. Becoming involved in such a project
often means a discount price for the testing.
This article has been written by a layperson trying to
interpret the scientific material available, and may have
over simplified matters as far as geneticists are concerned,
but it is a reasonably fair interpretation of the situation.
The costs of suitable tests are for the most prohibitive,
especially when the results are unlikely to progress your
research. At best you may come across some distant cousins
participating in a surname study. You could have just as
easily discovered them, by advertising your research interests
widely! At this time, the tests lack sophistication and
are far too reliant on the participating researchers knowledge
of their own surname ancestry to be even able to confirm
that when you find that distant cousin s/he is indeed who
they say they are! To blindly subscribe to the concept
may just be opening up yet another family history pitfall.
Bibliography
Chris Pomery; DNA and family history; how genetic testing
can advance you genealogical research
Ken Graves
Graham Jaunay BA DipT MACE AAGRA
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