Tracing paternal line with DNA testing

[Miss.ellie]

I've been reading up a little on this subject but I'm still not sure how to go about it. My brother and I are tracing our paternal line but we only have a strong theory concerning the parentage of our paternal grandfather.

Does anyone how you go about this and how much it costs, as we would like to prove or disprove our theory.

Thank you

[davidft]

As I understand it you have a male line from your grandfather (ie grandfather, father, your brother) and you have a possible name for the great grandfather. By far the easiest would be if your brother and a direct male line descendant of the alleged great grandfather could do a Y DNA test as there would be a strong correlation if true. However this requires you to be able to persuade the descendant of the alleged great grandfather to also take the test. If this was not possible you could get your brother to take a Y DNA test with a site like www.ftdna.com and compare it with their surname groups. However this is a bit hit and miss as
1. genealogical DNA testing is very much a minority think
2. most of the testers are actually American
3. not everyone who tests reveals their results

I would have a further look at the ftDNA website and see if there is a group for the surname you are searching and whether its worth going down this track.

Alternatively if the name is confined to a small geographical area you could put an advert in a family history magazine or the magazine of the appropriate local family history society to see if someone with a proven lineage back to the suspected person would also test

The ftdna.com website has a range of tests and prices to match worth a look, there are other testers but I have quoted this one as it is the biggest

Hopefully someone more knowledgeable in the subject will come forward and give some more suggestions

[Miss.ellie]

Thank you for your detailed answer, much appreciated. The family we're tracing is very complicated.

My paternal grandparents Harold and Joan were second cousins, that is Harold's maternal grandmother was the sister of Joan's father ( Beresford). The other Beresford sibling was named May, May married R Judd , and had one child Reg, reg has one son G.  We believe our grandfather was the illegitimate son of R Judd.

As G Judd, myself and my brother will have Beresford blood  , will this complicate determining the Judd heritage and thus determine the father of Harold. The only 'proof' that we have is the strong similarity between Harold and R Judd,at different phases of their lives and also some similarities between other members of the family which we believe are too strong to overlook as coincidence.

Any advice would be appreciated, thank you.

[davidft]

So if I have the families right it is

family 1 R Judd, Reg Judd, G Judd

family 2 grandfather, your father, your brother

You think your grandfather is the son of R Judd, there your brother and G Judd would be cousins once removed.

Therefore if all this was correct and the two took a Y DNA test at 37 or 67 markers it would show a very high correlation (http://www.familytreedna.com/faq/answers.aspx?id=8#511 has a little table showing how likely a match is at 5.). The higher number of markers tested the better more reliable results you will get.

So on the face of it looks like a good way forward - however I would wait and see what those more expert say in the next day or two

[Miss.ellie]

Thank you. Yes that's right, the thing is though does the beresford factor affect the results ?

[davidft]

Thank you. Yes that's right, the thing is though does the beresford factor affect the results ?

Not for this particular test, that is why I only mentioned the Y  DNA test as it only tests the genes passed down from father to son to grandson etc ie male line only

That is also why I keep saying your brother as you can not take this test being female

[Miss.ellie]

Thank you for clarifying, I read previously about the Y chromosome test and discussed with my brother who would be happy to take the test. We have previously relayed our theory to G who agreed there were distinct similarities in the photographs we showed him, so hopefully he may help us to clarify this mystery for once and all.

[davidft]

Good luck with whatever you decide and hopefully one or two of the more knowledgeable posters such as supermoussi  or DevonCruwys amongst others will see the thread and also comment

[Miss.ellie]

Thank you again for your help, much appreciated