Hi John, You seem to be quite knowledgeable about DNA interpretation. I must say I have really battled to comprehend the significance of the various results. We have a unique family name, Bridgeford/Bridgefoord, which through research has been centred around the Aberdeenshire areas of Scotland. We have several Bridgeford family trees which we can't link up, as documentation is no longer available from the early days in Scotland. In four of these trees, we have managed to find male descendants, and have had their DNA Y-chromosome tested, in a 46 marker test. The results are that two are related at MRCA 10 and MRCA 14 to my DNA markers. The third person is not related [here we presume that there is an illegitimacy somewhere and the name is carried through by the female link, and hence no DNA Y-chromosome match].
Is there some way we can determine at what point in time these trees converge, and at what accuracy. I believe that the MRCA 10 , for example, indicates that the convergence was 10 generation age. Is this correct? And what variance can be expected in terms of generations? The other thing that really puzzles me, is that when viewing results from Ancestry.com, for example, there are many people with MCRA values of 3 or 4, and no apparent surname association. After intensive investigation from both sides, there is no apparent link at all. It seems almost impossible to believe that our forefathers sired that many illegitimate children on overseas visits!!! Is there areas where the DNA matching is simply not true? I would be most appreciative if you would be able to answer some of my questions, or perhaps put me in contact with someone who can. Very Confused, Mike Bridgeford Plettenberg Bay South Africa -----Original Message----- From: hwedhlor [mailto:[email protected]] Sent: 17 July 2011 07:10 PM To: [email protected] Subject: Re: [LegacyUG] DNA entry Richard, MtDNA is not reported as a complete set. Each DNA testing company has different defined marker sets, but they all compare those sets to the Cambridge Reference Sequence (CRS), then report deviations from that sequence, not the entire list, which would include 569 values (bases) for HyperVariable Region 1 (HVR-1) and another 574 values for HVR-2 (Note that some testing companies define a 3rd HVR region, taking some values from the HVR-2 region and placing them in that third area). Personally I'm not at all interested in entering 1143 values. Instead I entered only "CRS" in the HVR-1 column for myself, as my HVR-1 values did not differ at all from the CRS values. In HVR-2 I entered only my five values that differed from the CRS. Allowing for 20 deviations from the CRS in each of the three recognized regions seems sufficient. I can't speak for the rest of the Legacy user base, but I think it doubtful any of them would vary from the CRS by anything close to 20 values in each of the three HVR columns. As for the values for each entry field, typically an mtDNA value is a 4-digit entry. That is three digits for the base location, plus a letter signifying the specific component (adenine, guanine, cytosine or thymine, represented by A, G, C or T). For example, if the CRS at location 195 is T, and the person being tested has a component at 195 of C, then the deviation would be reported as "195C". It is possible to have additional values (insertions) at a given location. In that case they would be reported using the base location (for example "195C") with the addition of a decimal and a number. For example "195.1C". Two insertions would be reported as 195.1C and 195.2T. Deletions (missing base location values) are also possible. In such cases the missing location is reported as a number followed by a minus sign. For example "195-". Using those notational standards it is highly unlikely that any give value would exceed 7 digits, so 10 is more than adequate. Regards, John Zimmerman Mesa, AZ On 7/17/2011 7:46 AM, Richard Van Wasshnova wrote: > You can't input your complete mtDNA in v.7.5.0.98 anyway. > The template only goes up to 20 entries (of 10 letters) in each HVR. > We'll all have to wait for the next update. > Legacy User Group guidelines: http://www.LegacyFamilyTree.com/Etiquette.asp Archived messages after Nov. 21 2009: http://www.mail-archive.com/[email protected]/ Archived messages from old mail server - before Nov. 21 2009: http://www.mail-archive.com/[email protected]/ Online technical support: http://www.LegacyFamilyTree.com/Help.asp Follow Legacy on Facebook (http://www.facebook.com/LegacyFamilyTree) and on our blog (http://news.LegacyFamilyTree.com). To unsubscribe: http://www.LegacyFamilyTree.com/LegacyLists.asp Legacy User Group guidelines: http://www.LegacyFamilyTree.com/Etiquette.asp Archived messages after Nov. 21 2009: http://www.mail-archive.com/[email protected]/ Archived messages from old mail server - before Nov. 21 2009: http://www.mail-archive.com/[email protected]/ Online technical support: http://www.LegacyFamilyTree.com/Help.asp Follow Legacy on Facebook (http://www.facebook.com/LegacyFamilyTree) and on our blog (http://news.LegacyFamilyTree.com). To unsubscribe: http://www.LegacyFamilyTree.com/LegacyLists.asp
