All genealogists find their lineage stops at some point…the proverbial brick wall. As records have been lost, burned or never existed to help us tunnel through that brick, a new tool in the genealogist’s toolbox, just may be the answer. That new tool is DNA testing.
DNA testing for genealogists began in 2000 and has rapidly grown ever since. That year, Bennett Greenspan, founder of Family Tree DNA, started the first company to sell DNA test kits to and for genealogists. Today his company handles the testing for the National Geographic Genographic Project and has the largest database for genealogists. Bennett is a genealogist. DNA testing continues reaching various milestones and has helped genealogists in many ways.
Through DNA testing, you may find a match between your surname and that of another tester who has a documented family tree that could add to your information. By finding other researchers with whom you have a common ancestor (a DNA match), you could focus on the missing generations between your families. ALSO, DNA testing rules out persons with the same surnames who are not a genetic match, thus allowing you to focus on lines that are definitely related to you.
The DNA results will not tell you the name, place, or time the common ancestor lived, but will tell you there is a common male ancestor between two or more testers. This is called the Most Recent Common Ancestor (MRCA) by geneticists.
Depending upon the number of markers tested and the quality of the match, DNA results can provide a time frame in which the common ancestor has a high probability of existing. Basically, the following list indicates the highest probability.
If there is a match for a…
…12 marker test, the MRCA is prior to 600 years ago.
…25 marker test, there is a 95% probability of an MRCA being within the last 600 years.
…37 marker test, there is a 95% probability of an MRCA being within the last 300 years.
…67 maker test, there is a 95% probability of an MRCA being within the last 150-200 years.
NOTE: A match is considered to be an exact numerical copy up to a genetic difference of four.
Genetic Difference is the numerical differences between two person’s markers. This is calculated in two different ways depending upon the particular marker. Most generally you can just subtract the two numbers in each marker (allele) to get the difference. When you have differences in fast mutating markers which have various parts to them (indicated by red on the Family Tree DNA websites (http://www.familytreedna.com/) and having a small alphabetic number after the name of the marker. EX: 464a or CDYb), these are often (not always) considered a difference of one although the various parts of the one marker could have differences in all parts. For example: 464 has several parts….a to g. If someone has the results below, they would still have a genetic difference of one.
Through DNA testing, you may find a match between your surname and that of another tester who has a documented family tree that could add to your information. By finding other researchers with whom you have a common ancestor (a DNA match), you could focus on the missing generations between your families. ALSO, DNA testing rules out persons with the same surnames who are not a genetic match, thus allowing you to focus on lines that are definitely related to you.
The DNA results will not tell you the name, place, or time the common ancestor lived, but will tell you there is a common male ancestor between two or more testers. This is called the Most Recent Common Ancestor (MRCA) by geneticists.
Depending upon the number of markers tested and the quality of the match, DNA results can provide a time frame in which the common ancestor has a high probability of existing. Basically, the following list indicates the highest probability.
If there is a match for a…
…12 marker test, the MRCA is prior to 600 years ago.
…25 marker test, there is a 95% probability of an MRCA being within the last 600 years.
…37 marker test, there is a 95% probability of an MRCA being within the last 300 years.
…67 maker test, there is a 95% probability of an MRCA being within the last 150-200 years.
NOTE: A match is considered to be an exact numerical copy up to a genetic difference of four.
Genetic Difference is the numerical differences between two person’s markers. This is calculated in two different ways depending upon the particular marker. Most generally you can just subtract the two numbers in each marker (allele) to get the difference. When you have differences in fast mutating markers which have various parts to them (indicated by red on the Family Tree DNA websites (http://www.familytreedna.com/) and having a small alphabetic number after the name of the marker. EX: 464a or CDYb), these are often (not always) considered a difference of one although the various parts of the one marker could have differences in all parts. For example: 464 has several parts….a to g. If someone has the results below, they would still have a genetic difference of one.
..................464a....464b....464c....464d
Tester 1: .....16..........17........17.........16
Tester 2: .....16..........16........16.........16
After finding a good match, it is very important to check your paper trail and to test a distant cousin of both testers who matched. In this case, go back to the oldest known ancestor and bring an all male line forward to the present on a son different than that of the person who tested. This could be a person you do not know and probably is. However, after contact and after getting to know them you may convince them to test, but you may have to help pay for their test. The idea is to confirm that your DNA is that of your paper trail and your surname. Since time began our ancestors have taken in the orphaned children of the neighborhood. Many adoptions and name changes have existed over these thousands of years without any written record…even into the 20th century. By testing more than one person on a surname, you can determine if any adoptions (formally or informally) have taken place.
After you have tested a distant cousin and proven your DNA matches his, then you are ready to compare your results with other testers to find more cousins. At this point you should be in contact with persons matching your test results and comparing your pedigrees.
If you find that both your lines are in the same general areas, then it’s back to basic genealogy research to find the paper trail which supports the DNA match. If you can’t find that common land area (county, etc), consider the brothers and uncles along the same branch of your pedigree chart. The two testers could be related through an uncle’s family who came to the area. Sometimes it is necessary to test the descendant of other people in the area who bear the same surname.
As more people test…and hundreds are doing so weekly…the number of potential matches will increase. The more matches you find the easier to narrow down your MRCA. DNA testing can be helpful for the present and even more valuable in the future.
These are exciting times and the field of genetics is moving quickly. It has been said that within the next twenty years genealogists will start with their DNA first and then work on the paper trail. At the rate genetics is moving this will happen sooner. More and more people are beginning to understand how genetics can help genealogy. Those who use this new tool no longer consider themselves genealogists, but are proudly called Genetic Genealogists.
If you have questions, please contact Emily Aulicino at Aulicino@hevanet.com
To order a DNA test and receive the reduced price through a Surname Project:
1. Go to the bottom right of this Blog and click on the FTDNA icon.
2. Where it says SEARCH on the right side, type in CAMPANIA
3. On the next page, click on CAMPANIA
4. Complete the form. Scroll to the bottom of the page and click on JOIN.
IF you know of a project, put that name where you see CAMPANIA above. If you are a female who wishes to test you cannot join a surname project. In that case type in CAMPANIA.
The CAMPANIA DNA Project is just one of mine and I can help you understand the results, etc. ALSO, you can move to a more relevant project at any time after you receive your test results without cost. You can be a member of more than one project at a time.
Email me if you have questions before you order your test. If you need help, I can call you or email you to walk you through the process.
Email me if you have questions before you order your test. If you need help, I can call you or email you to walk you through the process.
Copyright Aug 2008
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