I’m sure this fundamental question has been answered before, but I have missed it. If both my mother and myself have tested, can I match with someone from a known ancestral line of hers while she does NOT? OR, would the match mean that I MUST be related to this person through my paternal line?

You cannot legitimately match with someone who shares an ancestor with your mother's line without her showing the match as well. In most cases, if you have a match that your mother doesn't have, you can safely conclude that they are from your father's side. However, if the match is under ~7 cMs, it might be coincidental - identical by state - in other words a false positive, in which case it won't show up in either parent and is not worth pursuing. CeCe   www.yourgeneticgenealogist.com www.studiointv.com > From: [email protected] > Date: Tue, 15 Nov 2011 08:44:41 -0500 > To: [email protected] > Subject: [AUTOSOMAL-DNA] Fundamental autosomal DNA question > > I’m sure this fundamental question has been answered before, but I have missed it. > > If both my mother and myself have tested, can I match with someone from a known ancestral line of hers while she does NOT? OR, would the match mean that I MUST be related to this person through my paternal line? > > ------------------------------- > To unsubscribe from the list, please send an email to [email protected] with the word 'unsubscribe' without the quotes in the subject and the body of the message

Not entirely true. IBS can occur for segment over 7 cM, but are more likely with the shorter segments. Meanwhile, even if IBS, the majority of the segment could be IBD and as a result appear to "skip" generations appearing for both a grandparent and grandchild, but not the parent/child in between them. And in some cases, it may be an even larger segment share for the grandparent. Of course it also possible, and more common than many may think, that a persons parents may be distantly related which may make it even more difficult to draw conclusions from lack of a match. On Tue, Nov 15, 2011 at 4:02 PM, CeCe Moore <[email protected]> wrote: > > You cannot legitimately match with someone who shares an ancestor with > your mother's line without her showing the match as well. In most cases, if > you have a match that your mother doesn't have, you can safely conclude > that they are from your father's side. However, if the match is under ~7 > cMs, it might be coincidental - identical by state - in other words a false > positive, in which case it won't show up in either parent and is not worth > pursuing. > CeCe > > www.yourgeneticgenealogist.com > www.studiointv.com > > > > From: [email protected] > > Date: Tue, 15 Nov 2011 08:44:41 -0500 > > To: [email protected] > > Subject: [AUTOSOMAL-DNA] Fundamental autosomal DNA question > > > > I’m sure this fundamental question has been answered before, but I have > missed it. > > > > If both my mother and myself have tested, can I match with someone from > a known ancestral line of hers while she does NOT? OR, would the match > mean that I MUST be related to this person through my paternal line? > > > > ------------------------------- > > To unsubscribe from the list, please send an email to > [email protected] with the word 'unsubscribe' without > the quotes in the subject and the body of the message > > > ------------------------------- > To unsubscribe from the list, please send an email to > [email protected] with the word 'unsubscribe' without > the quotes in the subject and the body of the message >