Family Tree DNA Early Bird Sale through November 20th

Hello Project Members!

Family Tree DNA just announced their Early Bird Sale Monday October 24, 2022. This sale runs from Monday October 24^th to Sunday November 20^th.

I would like to encourage all Y-DNA test takers to consider upgrading to the Big Y-700 test. Continue reading to find out why!

First, let me explain the differences between the Y-DNA STR test (Y-37, 67 and 111) and the Big Y-700 test.

The Y-111 marker test examines 111 STRs. When two or more men have differences (mutations) in less than 10% of their STR values, we know that they descend from the same man. The Big Y-700 test examines 700 STRs. That is 589 more STRs in addition to the 111 that were already tested. The Big Y-700 test also searches for any SNPs (pronounced Snips) that have occurred in the DNA of the Y Chromosome. A SNP is a mutation in the genetic code of the Y Chromosome.

A SNP will occur in one man and one man only!

However, that SNP will be passed down to ALL of that man’s direct line male descendants, including their living Y-DNA test takers, through the Y Chromosome. Another SNP may or may not occur in another male descendant down the line. In theory a new SNP will happen on average every 3 generations.

This is not a hard and fast rule, however. A new SNP can occur for 3 generations in a row or not occur again for 5 generations from the first SNP occurrence. It is totally random, just like the STR mutations. We never know when a new SNP will occur, but when it does, we know for a fact that the mutation started with one man and was passed down through his Y DNA to ALL of his direct line male descendants.

If we get enough Big Y testers in any given line, we can figure out which man got the SNP originally. It takes quite a few testers to get to the point, however. How many does it take? Who knows. I have been working with Big Y for almost two years. I have tested my own family members and have analyzed the Big Y test results of my project members. Within all of these groups of Big Y testers the results have run the gamut.

I have seen where each of four sons of one ancestor got their own SNP. I have also seen where seven men have taken the Big Y test and not one of them got a new SNP that is different from their common ancestor. That common ancestor is between 5 and 8 generations back from each tester. Two of these testers are a father and son pair. Usually, fathers and sons will get a unique SNP from everyone else. However, that did not happen in this case.

While reading this you may be saying to yourself, “I know my entire line back to my “X” times great-grandfather. Why do I need to take a Big Y test?” My answer to you is because you are a kind person and you enjoy helping your distant cousins confirm their own lineages.

Your next question is “How can upgrading my Y-DNA STR test to the Big Y-700 test help my distant cousins? My answer? “Let me give you an example.”

Let’s meet the Cool family.

Joe Cool, Bob Cool and Rick Cool have all taken Y-DNA STR tests. They have all tested at the Y-111 marker level. These tests confirmed that they all descend from their oldest known ancestor, George Cool. This is wonderful information! They all descend from the same man and they know that man’s name.

But that is all they know. They cannot tell from a Y-DNA STR test how they are all related to each other. They can’t tell if they all descend from the same son or three different sons of George Cool.

Joe and Rick Cool have confirmed their lineage back to George Cool. Bob Cool has not. Bob Cool has only traced his line back to his 3 times great-grandfather, James Cool. Thanks to the Y-DNA STR test, by matching Joe and Rick, he knows he also descends from George Cool. However, he has some unknown ancestors in his line.

What if there was another test these three Cool men could take that would help Bob fill in those missing generations? Luckily, there is. It’s called the Big Y-700 test or Big Y for short.

Here are the lines of each Cool tester:

Joe’s line is: George Cool, Thomas, Henry, Thomas, George, Zachary, Grover, Mark and Joe Cool (Tester).

Rick’s line is: George Cool, John, George, Woodrow, Harry, Franklin, Abraham, Martin and Rick Cool (Tester).

Bob’s line is: George Cool, Unknown, Unknown, James, Andrew, Theodore, William, Robert and Bob Cool (Tester).

Joe, Rick and Bob all take the Big Y test. When the results come in, all three of them are on two different blocks just below George Cool’s known branch. They all got SNP ABC. Joe and Bob also got SNP XYZ which is a descendant SNP of SNP ABC. We can see this in branch/block format by looking at the Big Y Block Tree, which can be found on each tester’s DNA profile home page and shows newer SNPs as branches below older SNPs.

Since all three of them got SNP ABC, for now we can say that this SNP is from George Cool. Whether George is the originator of SNP ABC or whether he got it from an ancestor, we don’t know at this time. With more testing, we might find that answer, but for now we have no way of knowing.

Joe and Bob got SNP XYZ in addition to George’s SNP ABC. Rick Cool did not get SNP XYZ.

Because Joe and Bob got this additional SNP, we know that Joe and Bob have to have another ancestor in common other than George Cool. This will be a descendant of George Cool somewhere along the ancestry of Joe Cool.

Joe knows his entire line back to George. We don’t know where SNP XYZ originated, but we do know that it occurred somewhere in Joe’s line. We start by looking at George’s son, Thomas. Neither George’s son, John, nor any of his descendants, got SNP XYZ. Remember Joe Cool descends from son Thomas and Rick Cool descends from son John. Joe got SNP XYZ and Rick did not. Therefore, for right now, we are saying SNP XYZ originated with Thomas.

How will this help Bob find his missing ancestors. Well, for one thing, he can now fill in Thomas, son of George, as his ancestor. Because he got SNP XYZ and we are, for the moment, assigning that SNP to Thomas Cool, then Bob also has to descend from Thomas. Now Bob needs to investigate the sons of Thomas Cool. This is where Genealogy research comes in. Bob will have to look for any documents he can find to figure out which of Thomas’ sons was his ancestor.

“IF” it turns out that Joe’s ancestor, Henry, is also Bob’s ancestor, we can now say that SNP XYZ originated with either Thomas or Henry Cool. It did not occur further down because Joe and Bob descend from different sons of Henry Cool.

Assuming Henry Cool is also Bob’s ancestor, the Cool lines with SNPs now look like this:

Rick’s line is: George Cool (ABC), John (ABC), George (ABC), Woodrow (ABC), Harry (ABC), Franklin (ABC), Abraham (ABC), Martin (ABC), Tester-Rick Cool (ABC).

Joe’s line is: George Cool (ABC), Thomas (ABC & XYZ?), Henry (ABC, XYZ), Thomas (ABC, XYZ), George (ABC, XYZ), Zachary (ABC, XYZ), Grover (ABC, XYZ), Mark (ABC, XYZ), Tester-Joe Cool (ABC, XYZ).

Bob’s line is: George Cool (ABC), Thomas (ABC & XYZ?), Henry (ABC, XYZ), James (ABC, XYZ), Andrew (ABC, XYZ), Theodore (ABC, XYZ), William (ABC, XYZ), Robert (ABC, XYZ), Tester-Bob Cool (ABC, XYZ).

Remember that ALL of the descendants of George Cool in Joe Cool and Bob Cool’s lines got two SNPs. They got SNP ABC from George in addition to SNP XYZ which originated with either Thomas OR Henry. If we test a descendant from another son of Thomas and he also gets SNP XYZ, then we know that the SNP originated with Thomas Cool. If he doesn’t get SNP XYZ, then we know for sure that the SNP originated with Thomas’ son, Henry.

The bottom line is, Bob Cool would not have been able to fill in his missing generations and find his complete ancestry without Joe Cool upgrading his STR test to Big Y.

Rick Cool’s test was actually not necessary when all was said and done. However, we didn’t know that when the three Cool men decided to upgrade to Big Y. It could just as well have turned out that Rick and Bob descended from the same son of George Cool. This is one example of why we need multiple Big Y testers from any given line. We never know which two men, if any, will get a new SNP that differs from the oldest known ancestor.

I know this is a lot to read and a long-winded explanation. I am a teacher at heart. And now that I have learned how useful Big Y is, the teacher in me wants to enlighten all of you about Big Y as well.

Thank you for reading the entire post!

Please email me at beckygrizz@yahoo.com if you have any questions about the Big Y-700 test or any other DNA questions. I am happy to help!