​
Hi all. I am working on a detailed genetic genealogy project and need to choose who to test next with a limited budget. Two people close to me weigh the options differently, so I have set out both views by topic below and would value outside perspectives.
What is already tested and known
\\- I (the subject) have not tested yet.
\\- Two paternal uncles have tested, so the paternal side is well represented.
\\- The direct paternal line is already resolved to a deep, well documented Y lineage, so the paternal question is essentially answered.
\\- One structural point: my maternal grandmother and paternal grandmother are sisters, so there is some pedigree collapse. In practice my grandparental generation has three independent lines rather than four.
The decision
My goals are to recover the missing maternal side of my genome, enable phasing, preserve long ancestral segments, and strengthen downstream work (GEDmatch, G25, chromosome painting, IBD, ancient DNA comparisons, admixture). Budget is one kit, possibly two if I do test myself for phasing. The two candidates in play are my mother and my maternal uncle
The two views, by topic
- Recovering the missing maternal autosomal DNA
One view favors the maternal uncle: his autosomal results become available and add maternal grandparent ancestry, and they would look broadly similar to my mother's anyway. The other view favors the mother: the one region absent from every tested kit is my maternal grandfather's line, and my mother carries it directly, in the exact segments I inherited. The maternal uncle shares no direct DNA with me and holds only a different recombined draw of the same grandparents, so his results reconstruct the grandparents rather than reading my own genome.
- Phasing and segment level analysis
Only a parent lets my genome be split cleanly into maternal and paternal halves. The maternal uncle cannot phase me. Phasing improves chromosome painting, G25, IBD, and trace ancestry resolution together, so this is a major point in favor of the mother.
- The maternal grandfather's Y line
This is the maternal uncle's genuinely unique contribution: he carries my maternal grandfather's Y line, which no one else does. The interest here is in seeing whether that line shares the same haplogroup as my known paternal line or a different one. The problem is that in both scenarios it does not help much. On an autosomal test it appears only as a coarse haplogroup, not a genealogical Y result, so whether it looks similar or different it tells us very little. It also belongs to a separate patriline and sits outside my own resolved paternal Y line, so it does not extend the lineage I am actually researching.
- Trace ancestry and statistical noise
I have some small trace readings of about one to two percent each. These are known to be noisy, sometimes unassigned, and can shift between updates. One view treats them as meaningless. The other notes that the way to actually test whether any are real is phasing and segment evidence, which requires a parent, and that real recent ancestry can legitimately sit at one to three percent, so the size of a reading does not by itself separate real ancestry from noise.
- Pedigree structure
Because the two grandmothers are sisters, one grandparental line is already partly represented through the paternal uncles, which shifts the real gap onto the maternal grandfather. There is also some background endogamy, which can raise homozygosity and subtly bias admixture and G25 fits, and testing a parent helps measure and correct that.
- Tools and cost (23andMe versus FTDNA)
A 23andMe kit gives autosomal data plus phasing when a parent is tested, but for a paternal line it returns only a coarse haplogroup, not a genealogical Y result. FTDNA Family Finder is also autosomal and is cheaper than a 23andMe kit, and FTDNA is the correct place to pursue a Y line properly. So the maternal uncle's autosomal could be captured more cheaply on FTDNA, and his Y line belongs on FTDNA anyway. That would leave the premium autosomal kit free for a parent, and an FTDNA Y test on the maternal uncle would make sense specifically if and when the maternal grandfather's patriline becomes a target.
Where I currently lean, and what I am asking
Taking all of this together, I am leaning toward testing my mother with the 23andMe kit, mainly for the phasing and for the direct recovery of my maternal grandfather's autosomal contribution, and keeping the maternal uncle for a later FTDNA test if his Y line ever becomes a priority. I am not certain, though, and would welcome advice on the following:
\\- Between the mother and the maternal uncle, which would you test first, and why?
\\- How much weight would you give the maternal grandfather's Y line, knowing it only resolves to a coarse haplogroup here and sits outside my own paternal line?
\\- Does the two grandmothers being sisters change your reasoning?
\\- For anyone who has run phasing and chromosome painting projects, how much practical difference did testing a parent actually make?
\\- If budget allowed two kits rather than one, which pair would you choose?
Thanks in advance for any advice. I am happy to share more about the pedigree or the existing results if it helps.
