Naming pattern may be hints to ancestors' names

DNA won't tell you where a middle name comes from!!

The main thing I know about my Bisset line is that it is at least a real line of father to son, with no "non paternal events" where a name on the certificate is just that of the husband and not that of the father. How do I know this well I've matched with 6 others all with the same surname who are now all part of the Bisset DNA project. One of the matches is an almost perfect match only one small variation of 1 minor change in the 37 markers that we have tested. Both lines are from North East Scotland but we haven't found the paper link yet.

DNA is interesting but it won't really tell you that much, unless you have specific desire to prove a link between two people. Testing on your own will tell you relatively little and it can be quite a confusing and expensive process.

PS. I've moved this query and reply to the DNA forum. To see the previous forum click on the little (its actually virtually invisible) arrow to the right of "Alexander Bisset said:" in Jennie's message.

 

This discussion is now in the DNA forum so its the right place to discuss DNA topics.

You can see the Bisset DNA project online. This is the sort of results you get for Y-DNA ie: the male only line. This ONLY traces the male-to-male-to-male line the branch that most people concentrate on the one that's often called your surname line. Your father's father's father etc. The reason for this is biology, the Y chromosome is only past from father to son. Thus a technique was developed to look at this and be able to prove that if man A and boy B had different Y-DNA then man A couldn't be the father of boy B.

For family history research this helps group possible surname matches eg: in the Bisset DNA project we have group several groups of close matches where its 99%+ certain there is a common male ancestor. The differences just push back that ancestor to further in the past unfortunately probably further back than paper records were ever kept for "low born" people. Sadly that means whilst we might be able to find paper records proof of a match we may never find it.

On the other hand I am awaiting a result from a new test from someone who should be an 8th cousin according to the paper records. Now if its a "clean" line and there has been no "non paternal events" in between (ie: fathers name on paper records isn't actually the biological father) then the DNA test should prove a match and thus validate our research back to 1684 where some paper records are bit vague no definitive proof. By that I mean some of the paper records very strongly suggest that two boys are brothers one record mentions both the fathers and mothers name the other just mentions the fathers name, however they are just 2 years apart and the father's name only one is at a farm where there is a family death some 40 years later. So a fairly likely set of brothers but the paper records aren't 100%.

A Y-DNA test will prove if the new tester's family are indeed related to mine. However there may be a fly in the ointment if at any time between 1684 and today one of the sons in his direct line wasn't fathered by the persons name on the certificate. In that case we will get something that doesn't match at all. Now that doesn't disprove our paper research but it would mean that we can't use DNA to prove the result. Its a bit hit and miss in that regard. The paper research might be flawless, but the DNA might show that for at least one of the pregnancies down the years the mother didn't let on to her husband that he wasn't the child's biological father.

I trust this gives some idea of how Y-DNA can aid research. The other test is a "Family Finder" test. However I'll type up something about that in another message as this one is getting long enough as it is

 

It's down to biology. All humans have two "sex" chromosomes and you are either XY or XX. If you have an XY chromosome pair you are a male and if you are XX you are a female that's the biological thing that determines our gender. Now when a child is conceived (the how the child is conceived is beyond the scope of this message, although the interested reader will find the internet full of examples of how this process takes place ) that child receives one sex chromosome from its father and one from its mother. The mother will always pass on one of her X's and if the father passes on his Y then the child will be a XY and thus a male if the father passes on an X then the child will be a female. That is how biology works.

So for family history purposes and the 10-12 generations we are often interested the fact that a father passes onto his sons the same Y chromosome unchanged (bar rare minor random mutations) means that a 10g grandfather is extremely likely to have the same Y chromosome as his 10g grandson who gets tested.

For females consider that even for two sisters there is a 50/50 chance that they would only be a 50% match for each other. Both sisters will match the X of their father because he only had one X to give, but they could have either of their mothers X's passed on. So between two sisters one could have one X and the other could have the other X meaning if they got tested they might only match 50% of their DNA.

 

Err no Robert. Your understanding of the mutations is correct but your definition of "fast" is somewhat out. A fast mutator on a Y-DNA test is likely to mutate at a rate of 1-2%. So the chance of a mutation in 8 generations is around 17%. This is precisely why they use these markers and not any of the other hundreds of thousands of possible combinations, they mutate sufficiently slowly to indicate a match in genealogical time frames.

At 8 generations you'd expect very very few mutation, yes possibly 3 or 4 but that then gets increasingly unlikely. "Fast" just isn't nearly as rapid as you make out.

Family Tree DNA has a chart that shows you precisely the percentage likelihood of a match given known generations of no match.

 

Yes I would concur with that. My concern was that less well informed people may jump on the idea that in just 8 generations there may be lots of changes, when in actual fact it is more likely than not that there has been no mutations between two related cousins.

My DNA proved, paper unproven cousin Joe Bissett, a forum member differs from myself in only one marker and it is one of the "fast" mutation markers. Given we know of no paper match in 10 generations there is a 99%+ chance of a common ancestor within 15-20 generations. Now we know that the families were living fairly close to each other in the 1600s but have no paper links.

On the other members of the Bisset DNA project we have one very close match to Joe who has 2 variants from myself. ie: he matches Joe in the marker where Joe and I differ, but not in another (or two I can't recall). However his family as far back as he has gone and Joe's family as far back as Joe has gone are living within half a mile along the same country road. So we are fairly confident that the match is one of the males we have a birth for but no mother's name. ie: we have a death naming father and mother (as is the Scottish custom) but a birth naming just the father. It's the same father's name and the location of death is within 2 miles of the birth location some 70 odd years earlier. However this is in the late 1700s so it's very difficult to be sure.

The DNA test however strongly suggests a match. I'd just be more comfortable with a paper record, eg: a land registry or something that showed the link. Luckily there is a relatively rare profession of Shoemaker to assist. However to date no paper records have been unearthed.

The other oddball in the mix is another close match with a family from the Edinburgh area which is some 130 miles away. So not sure on that one. What I would dearly love to achieve though is a DNA test from someone of the Bisset's of Lessendrum line who go back to the 1100s. As I am fairly certain that the NE Scotland Bissets will all trace their lines to that family (2nd/3rd/4th sons who didn't inherit the lands and titles).

 

A few more things to consider:

1. Is the number of repeats as likely to decrease as increase?
2. How likely is a 2-step mutation vs a 1-step mutation?

If the answer to the first question is Yes, then the chance of a difference between two cousins in X generations is (roughly) doubled.