This utility calculates probable relationship paths based on Autosomal and X-DNA Genetic Distances.
This application only works properly for 2 kits with a non-zero cM result for X.
Please explain what "non-zero cM result for X" means.
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Sign up to join this communityThis utility calculates probable relationship paths based on Autosomal and X-DNA Genetic Distances.
This application only works properly for 2 kits with a non-zero cM result for X.
Please explain what "non-zero cM result for X" means.
I assume you're talking about the 'Tier 1' Relationship Tree projection tool. Not many of us are gedmatch.com Tier 1 subscribers.
But a non-zero CM result for X is self-explanatory. The 'X' refers to the X chromosome, which men receive exclusively from their mother (the father gives them a Y-chromosome), and for women a copy is received from each parent. That allows some prediction of how exactly you might be related, as the X-DNA inheritance tree is only a subset of all possible ancestors. For more details, see this article: https://dna-explained.com/2012/09/27/x-marks-the-spot/. Note that the X-DNA ancestor tree depends on the gender of the person being tested.
A centimorgan (cM) is a unit of measurement of DNA strand length. When you share DNA with someone else, this is usually measured in centimorgans.
You can only use this tool between two kits that actually share (non-zero cM) some X-DNA.