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.

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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