My maternal great-grandmother’s maiden name, Leidesdorf, is relatively uncommon, and family lore is rich in fantastic tales about purported relatives from multiple European cities who were fabulously rich, extremely famous, and/or incredibly successful. Over three decades, I had accumulated information for seven different family lines with surnames that sounded like Leidesdorf, and I wanted to know if we might be related to them. DNA testing, available now at a reasonable price, seemed the best way to determine, once and for all, if the lines are linked. Such an approach potentially could save many hours (and money) trying to determine possible relationships using traditional genealogical tools.

Tracing Male Descendants

Some trees had no living male descendants, so I focused on tracing the male descendant lines. In some cases I had to expand to researching individuals on the female descendant lines. While female descendants or their lines could not take a DNA test, I sought their assistance to find a living male descendant. To organize my data, I developed a census of known family members with five headings; I first focused on tracing the male descendant lines. Family line; number of descendants on tree (male and female combined); number of male descendants with the name Leidesdorf (or variant); number of descendants probably still living (male and female combined); and number of living male descendants with known contact information.

Two trees had 11 and 14 living male individuals on whom I was able to obtain current contact information—and a reasonable hope that at least one would submit to taking a DNA test. Four of the trees, however, had only one to three living descendants (to my knowledge), and one had only a single living male descendant. Would he agree to take the test, and would one of the few individuals from the other trees agree as well? Finally, I had a tree for Meyer Leitersdorf from Leidersdorf, Peine, and Braunschweig Germany, from which I could not find a single living male Leidersdorf descendant. I spent some time tracing all lines on the tree and eventually found two living descendants, Susan in San Francisco, California, and Daniel in Uruguay. I found Daniel’s name on MyHeritage.com; to contact him I enlisted help from a distant cousin from a different side of my family who happens to live in Montevideo, Uruguay. Happily, he knew the family I was seeking. Neither Susan nor Daniel, however, knew any living male descendants with the Leitersdorf surname who could take the DNA test. With some additional research in the future, perhaps one will surface—if he exists.

Recruiting DNA Submitters

After completing the research, I created the Leidesdorf Surname Project at http://www.FamilyTreeDNA.com and invited people with that surname to take the DNA test. Although I did not expect many responses, I thought that posting the project would provide credibility as well as a “home” for the DNA results. I chose to make the project public, but to keep the results private and limited to the individuals who ultimately took the tests.

Next, I assembled a package to send to the living male descendants I had found, inviting them to take the DNA test. I created a cover letter introducing myself and the project; I also included the Frequently Asked Questions document to answer any questions they might have about the test and a descendants family tree chart showing the male descendants starting with the oldest ancestors.

I addressed each letter to a specific individual so they would recognize that I knew who they were and, thus, would see the project as important. I reasoned that a letter simply addressed to “Dear Possible Relative” or “Dear Relative” would not have the same effect. I sent copies of the packet by both postal mail and e-mail (when I had an e-mail address). Those sent by e-mail allowed me the opportunity for some quick feedback about interest and also allowed the physical letter (which would arrive a few days later) to serve as a reminder to respond to the project.

In some cases, recipients forwarded the e-mail to all the males on their branch of the tree and decided who would represent that tree. In a couple of cases where only one or two living male descendants were known, one person stepped forward. On a line where I found only one living male descendant, that person answered that he would be glad to submit his DNA. Of primary importance to me was the agreement to take the test from a Leidesdorf on my own family tree. Without that, I might be able to tell if some of the other trees were related, but would not know whether or not they were related to me.

Paying for the Tests

Summary

Of the five lines tested, the results conclusively proved that none of the lines are related within several thousand years. While the individuals on a given tree are related to one another, they were not related to anyone on the other family trees with the same surname. What is really puzzling then is how three of the trees all have roots from Pressburg, Austria, and two of them migrated to the Netherlands, yet none are related by blood. Given the fact that the five trees are unrelated, it is of some interest to see if we can figure out why some of the trees have like surnames and lived in the same towns but are unrelated. Did they take the Leidesdorf surname because they came from the geographic town of Leidesdorf in Germany? Could it be that the original women of each family line took on their fathers’ surnames when they had children? Or did they simply latch on to the name since special privileges were given to some family members by the Emperor of Austria? That will require not only genealogical research of the families, but additional historical information about the towns they inhabited.

When I shared the results of the tests with all of the living male descendants, not just the ones who took the DNA tests, they were very surprised, much as I was. One wrote back to say that while there appeared not to be any blood relationship, “having a name in common is culturally more important than having a common biological origin.”