10

There is a service to turn a physical chromosome position (measured in base pairs, "bp") into a linkage position (measured in centiMorgans, "cM") here: http://compgen.rutgers.edu/map_interpolator.shtml To get the cM for a segment given its begin and end positions, you would use the web site to convert each of the two positions into linkage positions and ...


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

No. MyHeritage DNA does not currently have a way to view just the triangulated matches. You have to find them yourself, remembering that if you have even one extra person on a segment that does not triangulate with the others, then the triangulation will not show up. This is what I recommend you do: Download your DNA Matches shared segments. You can do so ...


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 ...


5

There is no autosomal chromosome 23. The human cell has 22 pairs of autosomal chromosomes (termed chromosomes 1 through 22). The remaining two chromosomes of the cell nucleus are the sex chromosomes, the X and Y chromosomes. The sex chromosomes are called the X chromosome and the Y chromosome. There might be some software that labels the X chromosome as "...


4

Robert is correct that X passes unchanged from a father to daughter, but that would likely only reduce the overall number of crossovers by about 25%, as a son's X is from his mother and recombines normally. So that reduction in crossovers shouldn't increase the number of matches by very much. Update Dec 25: I posted some analysis I did that discusses the ...


4

Yep. Unfortunately, everything is possible. The genetic genealogy is very young field of human knowledge. And the provided graphs, comparisons etc. usually describes only very simple cases. For example, why do you think that you have ONLY ONE set of common ancestors between seventh cousin? It is possible that they are related through two bloodlines and the ...


3

Since you have two chromosomes of each pair, every match you have must be either: An IBD (Identical by Descent) match on your paternal side, An IBD match on your maternal side, or A false match. All the overlapping IBD matches on your paternal side will have to match each other and thus form a triangulation group, and all the overlapping IBD matches on ...


3

Hendrik Wendland has created a free tool for Windows (donations accepted) called MapS Converter that you can download. It can calculate genetic distances and convert between Build 36 and 37. It is available at Hendrik's MapS Phasing site: www.maps-phasing.com For example, in the screenshot, I entered the Base Pair addresses you gave as an example in your ...


3

I would encourage you to use DNA Painter for this purpose, rather than trying to make your own spreadsheet. It is essentially doing what you are doing but has much greater functionality – it is a tool designed for this task. DNA Painter website allows you to map specific segments to certain ancestors, where known, and help visually identify patterns. As you ...


3

This is my first attempt to answer a question regarding genetic genealogy -- although I've been doing it for nearly two years now. So this answer may be "amateurish". My ancestors come from an endogamous group (cousins married cousins -- most times > 2nd cousins), this greatly complicates the process DNA analysis. Particularly because tested matches that ...


3

Double third cousins would indeed have double the expected cM of single third cousins. The 3C in your table shows an average of 79 cM and a range of 0 to 298 cM, so double third cousins should average 178 cM with a range that could be from 0 to 596 cM. So double third cousins would move one away from needing triangulation to confirm the connection. Yes ...


3

The original source of the data in the chart you have provided is The Shared cM Project. On their website, they provide more details in a PDF about the ranges provided, as well as histogram distributions of shared cM. The most recent update is from 25 Jun 2016. For some relationships, they do not have enough data points to produce histograms, but the table ...


3

I'm by no means an expert on genealogical DNA (I probably know less about it than you do). I do seem to spend a lot of time looking at aspects of it that make no sense, though. That said, I'm going to go Holmesian here re: the impossible and the highly improbable. My guess is that you're looking at half-IBD matches here - your uncle and Joel, and the 3rd ...


3

Autosomal DNA is not a reliable detector beyond 5 generations. At 7 generations, you're expecting all her descendants to be 1/128th part Nancy (less than 1%), and thinking you all got the same 1%. But in reality, some descendant lines may have 2% from Nancy's mother, some lines may have 1% from Nancy's father, and others got zero or near zero. You have to be ...


2

Found another reason. These people only have enough total cM matching with Harry and Joel to be considered a match to just one of them. Yes, they do triangulate on this segment with both Harry and Joel, but this may be the only segment, or one of just a few, that matches to one of them. And only people considered to be matches have their segments included ...


2

I don't know if there's anything out there yet that is quite as robust as you're suggesting, although I'm also hoping to have something like this in the near future. For now, I'm using GenomeMate Pro. https://www.getgmp.com/ It imports data from all of the major sites... FamilyTreeDNA, Ancestry, 23andme, MyHeritage, and also GEDmatch & DNAGedcom. It's ...


2

You may upload all data you have to GENi.com or MyHeritage.com SaaS. They have unique and very powerful feature as finding of possible duplicates of persons. The question is that both services are limited in downloading of DNA, but it is possible too. Another option is to use GEDMATCH service and it's triangulation features, but they are no very user-...


1

There is a very useful plugin for Family Historian called 'Find Duplicate Individuals' that does the majority of what you want. It is not intended for genetic genealogy but is a general tool that I use frequently in my surname study which does unintentionally create duplicates. It creates a result set that looks like You can then run the merge individuals ...


1

I didn't see such type of calculator. But I can imagine the next algorithm: As we know each chromosome has it's own value for number of base pairs and cM. Also there is no direct connection between bp and cM, because bp is physical number of pairs and cM is the measure of recombination probability (or rate). Please note that we don't know HOW MUCH base ...


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