Why does WikiTree specify the husband of the female LCAN in mtDNA confirmation?

+4 votes
115 views
in Policy and Style by Marshall Moss G2G3 (3.4k points)
retagged by Maggie N.
What does LCAN mean?

1 Answer

+3 votes

Lynda: Possibly "Last Common Ancestor"? Just a guess.

Marshall: I know that the WikiTree DNA Project is underway with a large effort to reorganize and rewrite all the DNA Help pages. I'm sure it's going to take some time, though.

That specific example of an mtDNA confirmation you're looking at (at least I assume that's the one) is actually incorrect. The two individuals in the example have four different common ancestors dating back as far as a 6g-grandparent, but in all four relationship instances there are males within the ancestral branches between the two mtDNA test takers, so they biologically can't share a mitochondrial DNA MRCA. I don't know of a better confirmation example to point you to at this time, however.

My own personal (unsolicited) opinion is that is mtDNA is a marvelous tool to use as evidence in a negative hypothesis (e.g., "the documented maternal line between Xg-grandmother and living female Z is incorrect") or in a population hypothesis ("the maternal line is Southeast Asian"), but as a standalone method is too weak to validate a positive statement for genealogy. Even if a paper-trail matrilineal line is correct, within the more common mtDNA haplogroups literally a million of the 7.6 billion living people will share an exact full-sequence match. The mtDNA molecule is simply too tiny to allow sufficient variation to lend itself for use as positive evidence for a family tree. And that's with a full sequence match that includes a maximum of 15,447 base pairs. The HVR1 panel tests only 546 base pairs, and HVR2 only 576. It was the first genome sequenced and the first to be used for the testing of ancient remains. But for family trees, the information it can give us is somewhat limited.

by Edison Williams G2G6 Pilot (309k points)
Thanks, Edison. I am happy to know that there is some ongoing work to improve the DNA software.

I agree with your answer. However, my question was a simpler one that could not be given context within character limit. All that I was trying to get across is that the software spits back the male LCAN as the first option with an mtDNA confirmation. It seems to me that this has the potential to trip up folks that aren't as aware as we are. That male LCAN had nothing to do with the myDNA and thus has no role in the confirmation. A rather simple programming change could replace him with his female partner who actually was involved in the transmission of the mtDNA.

Marshall

Hey, Marshall. I kinda thought I might have been off-base...but now I know I'm lost. WikiTree doesn't do any app-driven, programmatic confirmation of DNA linkages; that's all done manually by adding source confirmations to all the profiles involved, and then manually setting the correct parents, up and down the line, as "confirmed with DNA."

Do you possibly mean the Relationship Finder, a la this link? If so, to my knowledge there's only one version of it. But now that you mention it, that really should probably display the most recent ancestral couple, not just the male...which I believe it does in all instances unless there is only a female ancestor identified in that generation. But I could be wrong about that.

If you're describing some app tool other than the Relationship Finder, could you possibly post a URL?

Marshall, You do not need to write the whole question in the heading. There is a good sized text box beneath the title line where you can write without worrying about size constraints.

Well, a 12,000-character maximum. So some wordy few of us have to worry about size constraints. Ahem....

angel

I wonder if anyone has ever hit the limit. smiley

Yes, that mtDNA confirmation example needs to be replaced with another.  The relationship finder defaults to the closest relationship and can’t yet restrict to only the direct maternal line which for Weatherford-199 is https://www.wikitree.com/treewidget/Weatherford-199/89#mt

And for Zimmerman-1613 is https://www.wikitree.com/treewidget/Zimmerman-1613/89#mt

They are both direct maternal line descendants of the same woman and share the same mtDNA (which confirms each mother/daughter relationship back to her).

Yes their very distant markers especially the  rare 1 that how ano who it belongs to

Related questions

+2 votes
1 answer
96 views asked Jan 5, 2019 in Policy and Style by Lisa Hazard G2G6 Pilot (170k points)
+5 votes
2 answers
146 views asked Nov 17, 2019 in Policy and Style by Richard Lanman G2G Crew (980 points)
+1 vote
0 answers
40 views asked Aug 25, 2019 in Genealogy Help by Steve Orobec G2G Crew (440 points)
+8 votes
1 answer
151 views asked May 17, 2019 in The Tree House by Mindy Silva G2G6 Pilot (609k points)
+7 votes
3 answers
+3 votes
0 answers

WikiTree  ~  About  ~  Help Help  ~  Search Person Search  ~  Surname:

disclaimer - terms - copyright

...