DNA testing - genetic genealogy

[Erato]

Tephra,

In short No because Y dna needs to come from the male line so unless you knew who his father was then you couldnt do it.  YOu could have MtA test done but this is not as accurate because this uses the female X chromosome which only passes through the female line

No, X chromosomes are passed through both male and female lines.  It is mitochondrial DNA that all [male and female] children inherit from their mother.  This is because egg cells are large and contain mitochondria while sperm cells are small and do not.  Therefore, all the mitochondria [which contain their own DNA] in the offspring come from the mother.

[acorngen]

Erato,

You are correct and I need to read what I am posting before I hit post   Through should have read from. 

Rob

[Tisy]

Hi,

No, not beyond reasonable doubt as to the actual father, but fairly certain as to the surname.

Our story is this;  my g-grandfather, William Henry Marshall was born to Mary Marshall in 1857 at the Barnsley Union Workhouse. The family legend is that he was the son of a wealthy man who became remorseful about his illegitimate child after the death of his wife and asked his solicitors to search for him so he could make financial provision for him.  He was told to "watch at the gates at 9 o'clock in the morning and he would see his father go by" and other snippets which leads us to believe that this man was someone important.   Mary Marshall was a domestic servant.  There is evidence that William Henry's fortunes improved somewhere between 1891 and 1901 - he went from being firstly a coalminer to glasspresser and suddenly in this period became the owner of a business - a newsagent and stationer.  He sent my grandfather to grammar school.  The family progressed rapidly after that and became fairly wealthy, but we never knew the name of his projenitor.

We decided to do the Y-DNA test and my brother's DNA was sampled.  We have many close matches to people by the name of Wood or Woods, all of whom originated in the northern counties of England.  The closest is to someone who ancestor came from Matlock in Derbyshire in the mid-1600's.  It is a "genetic distance 4" match, which means he has 4 differences in the number of allelles on his markers, i.e. about a 7 generation back common ancestor.  Unfortunately he has not been able to establish just who his ancestor's family is  - John Wood left Derbyshire in the late 1600's (possibly a Quaker) and settled in New York State.  It was probably his father (William) who was our common ancestor. I am now indexing all of the IGI extracted records for the name Wood and its variants across the counties of Cheshire, Yorkshire and Derbyshire in an effort to see if these families were linked in any way back in the 1500 and 1600's.  Unfortunately because so few English people test, all we are getting is more American matches where they also don't know how they fit in to the U.K. families.

Tisy

[rondem]

The results of DNA testing can be vague. However, my only reason to have it done is to see how far back my DNA line goes and from which group of people I am descended. I presume I am R1b but I would like subdivided beyond that. Personally, I wouldn't expect to make any great genealogical inroad to the last dozen or so generations.

[acorngen]

Tisy,

How does the DNA tell you that you are connected to the particular person you believe?  Wood is such a common surname in England that you could be related to one of a thousand in the counties you are cross comparing. 

I think that people in the UK dont test their DNA because we have ample access to the records and don't feel so strongly about spending money on what is yet an unproven aspect of genealogy such as DNA.  If anything I believe DNA puts more obstacles in the way of research because you become focussed on that one thing similar to what you have

[Tisy]

Hi Genresearch,

In reply to your first question, we have a genetic distance 4 match to this person, whose name is Wood.  This means that there are slight differences in the number of alleles on four markers out of 67 - a very close match, and according to the geneticists we are definitely related - most likely a common ancestor about 7 generations ago.  We both did the deep clade test as well, and this has revealed that we both share the same subclade R1b1b2a1b4c1, L20.  We also have more distant matches to many other people by the name of Wood or Woods, mostly from the counties of Cheshire and Derbyshire.  There are other people by the name of Wood or Woods on all of the surname DNA projects we belong to, who belong to completely different haplogroups, and this is probably because of NPE's or the fact that surnames only came into use fairly recently.  If we had only had a match to one person by the name of Wood, we would not have been so certain because of course this person may have been descended from someone who was illegitimate.  The point of all of this however, is not so much the name but the fact that this person at least has a paper trail - we have nothing, which brings me to your next comment.

If you do not have a paper trail - in our case the father was not named on the birth certificate;  the Barnsley Union Workhouse archives have been lost;  the members of the family who may have known the truth are now deceased.   Where do you go?  DNA was our only option, and I am not sorry we have used it as now we have something to go on.  The fact that the father may have been a person by the name of Wood is significant, as it gives some credence to the family legend which I will not go into here for privacy reasons.  I also dispute your comment about DNA being an unproven aspect of genealogy.  You will need to join some of the forums dealing with genetic genealogy to see what I mean.

Cheers,

Tisy

[Nick29]

Tisy - if you apply common maths, then to go back 7 generations (about 250 years), each of us alive today in the UK would have 128 ancestors in our direct lines.  Bearing in mind that there are currently about 60 million people in the UK, compared to about 6 million in 1750, then it stands to reason that the majority of us will share an ancestor within 7 generations, because there just isn't enough people to go round. 

You can see that quite easily from posts in this forum - yesterday I posted something about a friend with an ancestor with an unusual name, who was 5 generations back in her tree.  Within 24 hours, I had a reply from a lady in New Zealand whose husband shared the same ancestor.  This is in a forum with 121000 members, about half of which are active.  Think about it.

[coombs]

I want to do a Coombs DNA project as I have some male cousins with the surname as I want to trace the family of George Coombs born about 1790, my 4xgreat grandfather.

[nickgc]

250 years ago for 7 generations is an extreme over-estimate.  A generation is considered to be 25 years to 30 years, usually the lower number.  This figures out to 175-210 years for 7 generations.  This would equate to the 7th generation ancestors of 25-30 year olds currently having children of their own having bee born in the early years of 1800. (Using a strictly linear interpretation.)

Check your own charts to show this; there will, of course, be outliers, but in general it works out.

Also see http://itotd.com/articles/226/most-recent-common-ancestors/
for some interesting discussion.

I have difficulty seeing what argument people seem to be trying to make against DNA testing.  It is just another tool, and the more people who use it, the better it might be for all of us.  At least the really bright people doing genetics think so.

Nick