10

It looks like this may be due to a difference in the Genome Builds (https://en.wikipedia.org/wiki/Reference_genome#Human_reference_genome) used between the two tools. GEDMatch reports that they store data in Build 36 format (https://www.gedmatch.com/gedwiki/index.php?title=DNA_Upload). Louis Kessler noted that MyHeritage raw data is downloaded in Build 37 ...


7

The "DD"-prefix simply means that they're a member of the Facebook group "DNA Detectives". It's a Facebook group for people who use DNA genealogy to track down family members. If you're on Facebook, and join that group you can contact the person using the prefix who might then be able to help with your research. There's a handy little Genetic Genealogy ...


6

mtDNA and X-DNA mostly are not related. If two persons share the same mtDNA haplogroup it just means that their common direct maternal ancestor lived ~10000 years ago (when this haplogroup was developed). It means nothing more. Of course, this person may be your sister, for example, or maternal aunt/uncle. But you can prove or disprove it by comparing your ...


6

The GEDmatch Relationship Tree is a wonderful idea the imaginative people at GEDmatch put together. No, there is not much documentation about it and it is still said to be a "work in progress", but it has been there for a number of years and does something few if any other DNA analysis tools do. It uses the two people that you give it, whose relationship ...


6

What I see often said is that any matching segments under 5 cM, if not under 7 cM, are more likely to be identical by chance rather than by descent, and should usually be disregarded as noise. A Small Segment Round-Up (Blaine Bettinger posted 29 December 2017 on his blog The Genetic Genealogist) Sharing Large Segments With a Match Does Not Validate Small ...


6

The colored segments are not drawn in terms of cM, but in million base pairs (Mbp), which are the number shown on the bottom of your graphic. The numbers at the bottom are very approximate in position. So your purple segment is drawn between 102.9 and 111.0 Mbp and your green segment is drawn from 149.4 to 154.6 Mbp. So the purple segment is 8.1 Mbp long ...


5

There are 46 chromosomes that come in 23 pairs, one from mother and one from father. You are talking here about chromosome pair 12. The way matching works is that it cannot determine whether the match is occurring from the maternal chromosome or from the paternal chromosome. It only determines that either the maternal or paternal chromosome is matching at ...


4

For your African ancestry, accounting for European: in project Dodecad, try calculator Dodecad V3 in project Ethiohelix, try EthioHelix K10 + French in project GedrosiaDNA, try calculator Gedrosia K3 For your Native American ancestry, in project Eurogenes, try comparing calculator Eurogenes K12 with K12b in project HarrapaWorld, try its one calculator ...


4

The different companies use different cM for the 22 chromosome pairs. GEDmatch's total is 3587 cM excluding X and Y. See http://isogg.org/wiki/CentiMorgan Note this is half of what the 44 chromosomes total. The way matches are done, companies cannot distinguish between the paternal and maternal chromosome of each pair, so the total cM for matching purposes ...


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

legacyfamilytreewebinars.com ran two fairly recent webinars that might be extremely useful to you, "Weaving DNA Test Results into a Proof Argument" by Karen Stanbury, and "Finding Missing Persons With DNA Testing", by Diahan Southard. You would need to buy at least a short-term subscription to the webinar site to view them, but in your situation, I suspect ...


4

The simplest and most likely cause of the lack of a match is that Alice is related to Bob and Charlie through different parents. If Alice inherited the 36 cM of DNA she shares with Bob from, say, her father, and Alice inherited the 82 cM she shares with Charlie from her mother, then there would be no reason to expect any matching between Bob and Charlie. ...


4

So what you've got is this: You are correct that there is a single segment, represented by the dark blue segment in the diagram, between 30 and 35 Mbp (Mega base pairs) that is the triangulating region and may have been passed down to all three of them from a common ancestor. And you are correct that it will extend into the light blue segments. But no, ...


4

Getting your DNA tested and uploading the data to GEDmatch.com were both great ideas for trying to find your half-brother. According to https://www.nytimes.com/2016/08/28/world/asia/south-korea-adoptees-325kamra.html, there is a nonprofit organization called 325 Kamra whose web site is https://www.325kamra.org/. They say their mission is "to reunite Korean ...


4

The advantage of more people testing is that you can use the cM ranges better. Here, your aunt matches full siblings with different cM totals, even though they have to be the same relationship to her. You are looking for relationships where both 503 and 348 cM are within the range. Using the Shared CM Project, these include: Great grand aunt/uncle. Great ...


4

Ignore the cM value offered by the One-to-One tool, as a cM is just a STATISTICAL APPROXIMATION, instead check the offered SNP comparison values, it should read: "100 Pct SNPs are full identical". FYI: The SNP count offered for the comparison CAN'T exceed the SNP count of the smaller AncestryDNA v3 kit. If you were to run the "DNA File ...


3

GEDmatch does not disclose its methodology for phasing at GEDmatch Genesis. But if you and your mother tested at different companies, especially different companies that use different chips, then it could be that GEDmatch Genesis only includes SNPs that it can phase that are in both sets of raw data. ISOGG has an Autosomal SNP comparison chart which I'm ...


3

A match on maternal haplogroup may indicate a common ancestor on the direct maternal line (mother, mother's mother, mother's grandmother, etc). The inheritance pattern for the X chromosome is more complex. This article explains: https://dna-explained.com/2017/02/07/using-x-and-mitochondrial-dna-charts-by-charting-companion/ Keep in mind that in the 1800'...


3

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. ...


3

We all have about 3400 cM of DNA. On average half gets passed down each generation. So on average 1700 goes to a child, 850 to a grandchild, etc. Sixth cousins are at the 6th generation, so every 6th generation child should average having 53 cM. Some 6th generation children will have more than 53 cM from the ancestor, and some will have less or even none. ...


3

Family Historian has a gedcom export plugin available that has a specific export option for this scenario. However, the free trial version does not allow the running of plugins and so may be an expensive option if this is a one-off exercise, but it is an excellent programme for storing all your genealogical data.


3

This is an extended walk through of the original high level walk-through (no screenshot and only for windows) posted by Steven Frank's Blog for Windows PCs of a way how to do this to convert it to 23andMe's Build 36 version with extended detail and screenshots. Login to your FamilyTreeDNA Download the Build 36 Autosomal and X DNA RAW Files Unzip the ...


3

It will help if your father is still alive and willing to test. If not, consider his siblings or your first cousins on that side. Your best hope is to find DNA first or second cousins, but work with what you've got. This requires a lot of luck, though you already know there will be no maternal first cousins (if she had half siblings, then test them!). ...


2

You might want to look over this blog article: Genetic Genealogy and the Single Segment. It discusses a few points one might want to consider when one matches another person on just one segment. One aspect touched upon there is how segment size changes as we match on more distant ancestors. It's true that we get on average half as much DNA on average from ...


2

You are right to suspect an Aunt/Niece or Half-Sibling relationship based on 1786.1 cM Estimated Autosomal DNA matched. You haven't specified if you know who your mother is too, but if you do, or for the benefit of others that might be in the same situation. I know for a lot of people in this situation it could be quite a sore subject depending on ...


2

I want to append to the answer that GEDMATCH now supports FTDNA's format (both - b36 and b37). And there is no need in conversion. But if you really need the conversion between the formats there are plenty of tools: http://www.y-str.org/2014/09/autosomal-dna-converter-nix.html http://www.y-str.org/2013/06/autosomal-dna-converter.html Please note that ...


2

If you order a 23andme kit for yourself and can get one of your first cousins or a sibling of your mom to also submit a 23andme kit, you can deduce which cousin matches might be related to you through your father's side by triangulating which cousin matches are from your mother's side. Also if you are male, have a look at your ydna / paternal haplogroup, ...


2

If you know a programming a little bit (or better :-) you can use your skills to write simple parser. The best choice is to use language like python and already finished module for GEDCOM parsing (like https://github.com/nickreynke/python-gedcom) It is really not hard task to strip all unused information from GEDCOM because it is plain text file. One can use ...


2

This can happen even with full siblings of the same parents. Each parent has a chromosome 18 from each of their respective parents (the grandparents). Let's call the father's pair 18pp (paternal-paternal), and 18pm (paternal maternal), and the mother's 18mp (maternal-paternal) and 18mm (maternal-maternal). Now imagine three children who inherit from each ...


2

Res Privata is a venerable application for stripping non-vital data, especially for living people, , and free for non-commercial use. It is no longer has a website and I doubt it's supported, but it's available for download at the Family Historian User Group website. However, it won't filter non-blood relatives; and I'm not aware of a free utility which ...


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