Generational Surnames and Autosomal DNA Matching

 

Generational Surnames and Autosomal DNA Matching

By Roberta Estes

My interest in this topic is due to the number of adoptees I work with. DNA testing for genetic genealogy often represents the best, if not the only hope to adoptees of finding their genetic families.

I'm working with a woman who has two possible surnames to work with. Both are possibilities and the answer could be that neither of these surname is the right one. However, I've managed to put together some genealogy on both lines and I wanted to know how often people are finding matches in the genealogy data bases at Family Tree DNA and at 23andMe for their surnames represented by their parents, their grandparents, and their great-grandparents. For this exercise, I don't care how many matches to each surname they have, only IF they have any match to that surname.

For example, if your parents surnames are Smith and Jones, for example, and you have any matches that include the surnames Smith or Jones in their surnames listed as their ancestors, the answer is yes. If both Smith and Jones have matches, then you have 2 for 2 in the first generation. 

 

The second generation, grandparents, includes 4 surnames, the 2 represented by your parents plus two more, your mother's mother's surname (Anderson) and your father's mother's surname (Ferverda), for a total of 4. If Smith and Jones are already represented, then we need to determine if Anderson and Ferverda have matches. Let's say neither do, so for this generation, you have 2 of 4 possible. 

 

For the great-grandparents generation, we add 4 more ancestors, for a total of 8. Let's say that those surnames are Moore, Brown, Quincy and Scott and let's say that only Scott shows up in the list of surnames of your matches. So for this generation you have 3 of 8, your two parents, plus Scott.

The real question here is what is the likelihood that someone who is adopted will find their biological surnames in the surnames listed by their matches.

An ad hoc survey on both the ISOGG and the DNA-Genealogy lists in January 2012 received results for a total of 57 people who had been tested. A couple of people provided only partial information for a variety of reasons, so the totals in each group are slightly different.

Of the group who replied, for the first generation, their parents, the following was found:

• 20 people had no matches to their parents surnames
• 21 people had one match to their parents surnames
• 14 people had matches to both of their parents surnames

What this means to adoptees is there is a 38% likelihood that none or one of your parents surnames are represented in your matches. There is a 25% likelihood that both of your parents surnames are listed. Overall, there is a 64% likelihood that you will find at least one of your parents surnames listed in your matches. Of course, the question remains, which surnames are which.

Moving to the second, grandparents, generation we find the following.

• 16 people had zero matches to any of their 4 grandparents surnames
• 14 people had 1 match to their 4 grandparents surnames
• 11 people had 2 matches to their 4 grandparents surnames
• 7 people had 3 matches to their 4 grandparents surnames
• 6 people had matches to all 4 of their grandparents surnames

This means that there is a 30% chance that none of your parents or grandparents surnames are found among your matches. However, there is also a 70% chance that at least one of your grandparents surnames will be found among your matches. There is only a small chance, 7%, that all 4 of your grandparents surnames will be found among your matches.

Moving to the third generation, great-grandparents, we find the following:

• 11 people had zero matches to any of their 8 great-grandparents surnames
• 9 people had 1 match to their 8 great-grandparents surnames
• 6 people had 2 matches to their 8 great-grandparents surnames
• 12 people had 3 matches to their 8 great-grandparents surnames
• 7 people had 4 matches to their 8 great-grandparents surnames
• 4 people had 5 matches to their 8 great-grandparents surnames
• 2 people had 6 matches to their 8 great-grandparents surnames
• 4 people had 7 matches to their 8 great-grandparents surnames
• 1 person had matches to all 8 of their great-grandparents surnames
  
  

There is a 20% likelihood that none of your parents, grandparents or great-grandparents surnames will be found among your matches. However, there is also an 80% likelihood that at least one of those 8 surnames will be found among your matches. 

 

The results of the 3 generation, 8 surname survey, when plotted, take the shape of the traditional bell shaped curve, with a lump that would likely smooth out with more samples. Twenty one percent of the people will find 3 of their 8 grandparents surnames among their matches.

Most people told me where they tested, or I could easily discern the information due to the test name. Many of them also included their total number of matches. The total of matches at 23andMe was, as a rule, was between 4 and 5 times the number of matches at Family Tree DNA. However, the commentary was pretty uniformly that people were disappointed with the contacts, or lack thereof, at 23andMe, in general, and when contact was made, that many had either no interest in or little information on their genealogy, rendering the contact useless or nearly so. One person wondered why someone would test at Family Tree DNA if they weren't interested in genealogy, so the response problem is not unique to 23andMe clients.

Of the people who responded to the survey, 13 of them had tested at both 23andMe and Family Tree DNA. Those results are included separately. Of these at the 8 surname level, there were a total of 21 matches at Family Tree DNA and 34 matches at 23andMe, so testers are obtaining more surname matches at 23andMe, but only about one third more, not in proportion to the 400% to 500% more matches than at Family Tree DNA. This is likely a direct reflection of the number of people at 23andMe that are interested in the health information and not in the genealogical aspect. However, one would think that if they went to the trouble to enter their surnames, they would have some interest in family history.

Interesting aspects were that maybe half of the people had some complicating factor, such as a highly endogamous population or a patronymic population, both of which clearly affect the potential of finding matching surnames. Equally as interesting was the one man who had no matches for any of his 8 grandparents surnames but had relatively "vanilla" colonial American surnames. 

 

As both data bases increase in size, I would expect the numbers and percentages of matches to rise as well. The message here is that today, in January of 2012, for adoptees, there is about a 38% chance that one of your parents surnames is found among your matches, a 64% chance that one or both of your parents surnames will be found, a 70% chance that one or more of your grandparents surnames will be found and 80% chance that one or more of your great-grandparents surnames will be found.

This blog is © History Chasers
Click here to view all recent Lost Colony Research Group Blog posts

FTDNA offering special prices for Y-DNA upgrades

Y-DNA Upgrade Sale at Family Tree DNA

Those of our readers who have already Y Chromosome tested at Family Tree DNA of Houston, TX will be interested to learn of this special temporary price on upgrades.

FTDNA is currently offering special prices for Y-DNA upgrades. The table below compares the regular surname group rates with the sale prices.

The promotion won't last long. Kits need to be ordered and paid for by midnight on July 19, 2010.

Click on the link below to go to the FTDNA web site. Then log in to your personal page and click on the special offers link in the left hand navigation bar.

Click for more info

This blog is © History Chasers

Click here to view all recent Searching for the Lost Colony DNA Blog posts

Anita Wills Talks Genealogy - Podcast

Host Anita Wills talks Genealogy and answers questions from callers. Tips on genealogy and how to successfully research and document your roots. Excerpts from books, Pieces of the Quilt: The Mosaic of An African American Family, and Notes And Documents of Free Persons of Color.

http://www.blogtalkradio.com/Anita-Wills


© History Chasers

Click here to view all recent Searching for the Lost Colony DNA Blog posts

Family Tree DNA Holiday Prices are Now in Effect!!!

Dear Family Tree DNA Group Administrator,

In keeping with our end-of-the-year tradition, effective November 26th, 2008 we'll institute special pricing at Family Tree DNA for your new-kit-purchasing participants.

The products that will be offered at the special prices are:

	Y-DNA37	$119
	Y-DNA37+mtDNAPlus	$199
	Y-DNA67	$218
	Y-DNA67+mtDNAPlus	$308
	mtDNAPlus	$139
	Full Genomic mtDNA	$395
	SuperDNA	$613

This offer is good until December 31st, 2008 for kits ordered and paid for by that time.

http://www.FamilyTreeDNA.com

"History Unearthed Daily"

+1-713-868-1438

Family Tree DNA Reporting in From Houston

Dear Customers,

As a follow-up to our letter informing you of the level of preparedness Family Tree DNA established regarding the coming of Hurricane Ike to Houston, we are coming to you now to update you on our status post-Ike.

a) As you may know, all of our standard Y-DNA and mtDNA tests are processed at the lab in Arizona, and therefore, this processing has not been affected at all.

b) Also, as we advised previously, we have taken appropriate measures to safeguard and protect the data and our servers and therefore all computer systems are in place and functioning normally. You may have noticed that our web sites have been up, available, and are running normally as they were before and during the storm.

c) The building where Family Tree DNA's offices and Houston laboratory are located is without power, like most of Houston office buildings, and sustained damage, like so many other Houston office buildings. This means that the building will be closed for the next few days until it is ready for tenants to return. Despite this situation, several members of our staff have worked over the weekend to transfer equipment to other locations so that our normal office operations can resume on Monday, or at the latest on Tuesday, from an alternate location. All postal mail will be picked up normally at our local post office, so that kits can be checked-in and processed normally.

d) The coming days will allow us to have a better assessment of when our Houston lab will resume normal operations, at which point we will be back to you again with additional information about any delays in delivering results for the advanced tests that our lab processes in Houston. (Advanced panels, FGS and Deep Clade Y SNP's)

Please forgive us if in the next few days we don't meet our standard level of customer service as to e-mails and phone calls. We will be back to normal as soon as possible. We appreciate your continued support .

E-mail us anytime!

Bennett Greenspan	Max Blankfeld
President	Vice-President, Operations and Marketing
bcg@familytreedna.com	max@familytreedna.com

http://www.FamilyTreeDNA.com

"History Unearthed Daily"

713-868-1438

Scroll to the Bottom to View Interesting Videos

There are several interesting videos at the bottom of this page I would like to point out. Several about the Lost Colony and one about the upcoming Henry Louis Gates Jr.s' African-American Lives2 which will be shown in Feb. Plus an interview with Bennett Greenspan, CEO of Family Tree DNA of Houston.

DNA Tests Find More Branches Than Roots

By RON NIXON
Published: November 25, 2007

HENRY LOUIS GATES JR., whose PBS special “African American Lives” explores the ancestry of famous African-Americans using DNA testing, has done more than anyone to help popularize such tests and companies that offer them. But recently this Harvard professor has become one of the industry’s critics.

Gates says his concerns date back to 2000, when a company told him his maternal ancestry could most likely be traced back to Egypt, probably to the Nubian ethnic group. Five years later, however, a test by a second company startled him. It concluded that his maternal ancestors were not Nubian or even African, but most likely European.
Why the completely different results? Mr. Gates said the first company never told him he had multiple genetic matches, most of them in Europe. “They told me what they thought I wanted to hear,” Mr. Gates said.

An estimated 460,000 people have taken genetic tests to determine their ancestry or to expand their known family trees, according to Science magazine. Census records, birth and death certificates, ship manifests, slave narratives and other documents have become easier to find through the Internet, making the hunt for family history less daunting than in years past.
Yet for many, the paper or digital trail eventually ends. And for those who have reached that point, genetic DNA tests may help to provide the final piece of the puzzle.

The expectations and reasons for taking the test vary. For some, the test allows them to reconnect with African ancestors after centuries of slavery wiped out links between African-Americans and their forebears. Others want to see if they have links to historical figures like Genghis Khan or Marie Antoinette. For still others, it’s an attempt to fill gaps in family histories and find distant cousins they might not otherwise have known.

The demand has spawned an industry. Almost two dozen companies now offer such services, up from just two or three only six years ago. The field is so hot that private equity investors have moved in: Spectrum Equity Investors recently bought Ancestry.com, an online genealogy site, for about $300 million shortly after the site added genetic testing as a service.

But as the number of test takers and companies has grown, so has the number of scientists or scholars like Mr. Gates who have questioned assertions that companies make about their tests. One of the most controversial issues is the ability of the tests to determine the country or the ethnic group of origin for African-Americans or Native Americans.

Mr. Gates, director of the W.E.B. Du Bois Institute for African and African American Research at Harvard, said his experience and similar stories from others have prompted him to enter the field.

Mr. Gates recently teamed up with Family Tree DNA, a DNA testing and genealogy firm in Houston, to provide genetic testing and genealogy work for African-Americans. The new venture is called AfricanDNA.

“What we hope to do is combine this with genealogical and other records to try to help people discover their roots,” he said. “The limitations of current genetic DNA tests mean you can’t rely on this alone to tell you anything. We hope to bring a little order to the field.”

Full Article Here:

www.nytimes.com/2007/11/25/business/25dna.html