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10

This could also be explained if the parents share DNA. If you took the same test with your father and it also was > 50%, it could indicate they are distantly related. A single shared chromosome could appear as ~52%. Even if dad only shows 50%, he could have passed the shared DNA but mom did not pass it down, so it would overlap with the DNA mom did not ...


8

It's statistics. "Accurate" simply doesn't apply: a prediction may be 99% likely, but that will not mean a thing to that 1 in 100 where it fails -- and you have no way of knowing which group you fall into. More specifically, the ancestry timeline on 23andMe makes certain underlying assumptions that may or may not be true. One assumption is that their ...


7

DNA inheritance is very random in terms of how much DNA you get from each ancestor, due to genetic recombination. This basically means that although you get close to exactly 50% of your autosomal DNA from each parent, the amount you inherit from each grandparent, great grandparent, etc. will be different. I was able to test three of my grandparents and I ...


7

Unfortunately, the DNA companies imply way more accuracy to their estimates by including percentages to one decimal point. Let me rephrase your results as they should have been stated: My father is from 85% to 100% European (85% to 100% Ashkenazi, 0% to 10% Baltic, and 0% to 10% Italian), 0% to 10% West Asian, and 0% to 5% Central Asian. My mother is 80% to ...


6

First a comment on terminology – AncestryDNA and none of the autosomal DNA testing companies do "DNA sequencing". They do use single nucleotide polymorphisms (SNP) and/or short tandem repeats (STR) testing to look at areas of common variation in the genome. But just to be clear, these companies are not doing sequencing of any significant part of ...


5

What you are observing is normal. There is enough randomness, even between siblings, that they may show up as different relationships at 23andme and other companies. 23andMe estimates your relationship with your matches using some criteria based on number of matching segments, total cM, and larger cM matches. Second cousins have a large possible range and ...


5

The sex chromosomes are likely what make up the discrepancy. I'm guessing you are male. Females will share exactly 50% of their DNA with each parent, since they inherit 22 autosomes from each parent, and an X-chromosome from each parent. Males will share slightly more DNA with their mother than their father, since they also inherit 22 autosomes from each ...


4

The difference between a DNA test for genealogy and a WGS (Whole Genome Sequencing) test is that the test for genealogy obtains values for about 700,000 SNPs (Single Nuleotide Polymorphisms), whereas the WGS obtains the values for all 3 billion positions in your genome. For genealogy purposes, the 700,000 are enough, because they are picked from among the 10 ...


4

You want autosomal DNA because that is where you get ethnicity estimates. If, as ColeValleyGirl points out, this ancestor is your father's mother's mother's mother, then his mtDNA (along with any of his siblings') will be the same. Your mtDNA will be your mother's, so not helpful. If that is the case and the mtDNA is one that is from the ethnic group you ...


4

The key point you mention is that you and your sister share both half identical and completely identical regions of your DNA. Only full siblings will share significant amounts of completely identical regions. Half siblings will not. The chromosome browser in 23andMe will distinguish these for you. Full siblings share about 50% of their father's DNA and 50% ...


4

Jim Bartlett recommends using the 23andMe's "Yes" feature to develop your Triangulation Groups. He suggests you download all your segment matches and sort them in a spreadsheet. Then he says to work down your list starting from the first match, click on the hyperlink that takes you to your match's page, use his ICW list and mark each "Yes" in your ...


4

GEDmatch has two ways of getting the raw data from 23andme. If one of them doesn't work, the other one might. There have been no changes to the data format that GedMatch can't handle. One way is a new one: "fast & easy". I have not used this, so cannot give detail. In short, though, from GedMatch you are routed to 23andMe's site to give ...


4

"Acrosomes" just means that those five chromosomes are acrocentric: the centromere, or where the two single (haploid) chromosomes join together, is very close to one end of the chromosome than the other. The "p" or short arms are really short. The significance to genealogy isn't that they're acrocentric, but that they're heterochromatic. ...


4

Since you're asking about foreign governments as opposed to the United States, there's basically three answers as of right now: There isn't any. It may not invade your privacy, but your DNA may allow someone else's to be. It may not invade your privacy now, but it may in the future. Before I elaborate on those, I also want to highlight the fact that with ...


3

It's often difficult to ascertain relationships precisely from individual pair-wise matches (or even from 2 of them), in the absence of family tree knowledge. From the DNA Painter Shared CM tool, one relationship that fits the numbers is if the "grandfather" is your great-grandfather, and the "grandson" your first cousin once removed (1C1R). But, I suspect ...


3

There is a very useful table of average percentage sharing for relationship on the ISOGG Autosomal DNA statistics page. It shows the average (across a great number of different people, in theory) shared percentage value and the most common relationships the percentage is associated with. Any particular relationship of two particular people will have a ...


2

One tool quite a few genealogists use for visually displaying connected relationships in a graph is NodeXL. NodeXL Basic is a free addin-in for Microsoft Excel. The first person to blog about using NodeXL for genealogy was Shelley Crawford in 2017. She describes all the steps she took to use NodeXL to visualize her Ancestry DNA matches. Shelley goes into a ...


2

From the The Shared cM Project 3.0 tool v4 it appears that 45.5% equates to 3,394 cM. On the same page this suggests that you and your "half sibling" are: quite low within the range (3,330 – 3,720) for a parent-child relationship; fractionally higher than the range (2,209 – 3,384) for full siblings; and much higher than the range (1,317 – 2,312) for half ...


2

Your father got his one X from your grandmother. Your cousin's father also got his one X from your grandmother. The two fathers would on average match 50% since your grandmother's 2 X's recombine when passed to her sons and they each get random parts of those 2 X's. Since you and your cousin are both female, you would both get your fathers' complete ...


2

Without some additional information, no, you can't tell which of her parents you're related to based solely on the X-DNA match. You need to review your shared matches with her. Can you figure out how these people are related to her? Can you ask her how they're related to her? Once you know which parent those people are related to her through, you'll know ...


2

It will not affect your results. As long as you are hydrated enough to produce enough spit, you're good. From numerous conversations on various genetic genealogy groups, where employees of different testing companies have weighed in, the only situations to avoid are: Eating too soon before filling the tube. Because of contamination, not because it ...


2

Each genealogical testing company selects a proprietary portion of the approximately 700,000 SNPs to include in their test and this changes over time with different versions of their test as they evolve: 23andMe v3 11/2010 to 11/2013 v4 11/2013 to 08/2017 v5 08/2017 to at least 01/2020 according to their API since 11/2007 Ancestry v1 01/2012 to 05/2016 ...


2

It really is very simple. Everyone has two pairs of grandparents and 4 pairs of great grandparents and 8 pairs of great great grandparents. First cousins share a pair of grandparents. Second cousins share a pair of great grandparents. Third cousins share a pair of great great grandparents. The 4 people could be a third cousin of, for example, your Mom's 2nd, ...


2

Although WATO trees have been suggested (including by me) as your best hope, I don't believe that even they will be adequate to the task you propose. I'll go so far as to claim that it can't be reliably done using only DNA match data. Once you get beyond the close relationships of parent/child, sibling, and maybe 1st cousin, there are too many possible ...


2

It sounds like DNA Painter's What Are The Odds (WATO) tool might be of help. It helps you figure out how a target person is related to a set of other people who's relationship is already known, based on their DNA. You can read more about it here. There is also a version 2 that's currently in beta, but I can't speak to the new features it has.


2

I suspect you are seeing what is described at While You Were Sleeping: 23andMe Disrupts DNA Relatives: 23andMe has tightened their DNA Relatives cap, reducing the maximum number of accessible DNA matches from 2000 to 1500, without directly notifying all customers. While in previous years, customers could overcome the 2000-match limit by sending all of one’s ...


2

R-L165 is a subclade of R-L51 so you two definitely have a common straight line male ancestor. But the real question is how many generations back is your most recent common ancestor (MRCA). The only thing you know from the 23andme test data is that you both have R-L51 in common. That means you have an MRCA on the straight male line sometime within about the ...


2

Yes, 331cM seems too low to be an uncle. Uncles/Aunts are usually in the 1200 -> 2200 cM range. DNAPainter's Shared centiMorgan tool is a great way to look at possible relationships. For 331cM of shared DNA, it suggests the following possible relationships: [48%] Half GG-Niece/Nephew or Half GG-Aunt/Uncle or 2C or Half 1C1R or 1C2R [46%] Great-Great-Aunt/...


1

First, as already indicated, you need to be sure they're the same person. Second, you need to compare apples & apples - although 23AndMe made the unfortunate choice to show matches primarily in %, they also show cM (total and segments), which is the standard. On Ancestry, you may need to click through the match numbers to see the pre-Timber match levels. ...


1

Are you sure your mystery man is the same person on both sites? How do you know? 8% shared DNA (as per the 23andme results) could be related to your Dad as: (figures from https://dnapainter.com/tools/sharedcmv4/597) As you say, 3480cM is almost certainly the son of your grandfather. So your first step should be to attempt to verify that the 'mystery man' on ...


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