May we agree on a category name for phased autosomal DNA?

+10 votes
Autosomal DNA testers who have also tested both of their parents have the extraordinary advantage of working with phased results.  This allows them to confidently use matching segments as small as 4 cM (or possibly smaller) with others who also have phased results. GEDmatch has a simple to use phasing tool.

May we agree on a category name for such testers in WikiTree (so they can be found)?  Or would a tag be better?

Would simply "phased" work?  I find it interesting that there seems to be no standard for the abbreviation of autosomal DNA.  Like some others, WikiTree uses auDNA, but atDNA and aDNA are also popular.
in Policy and Style by Peter Roberts G2G6 Pilot (521k points)

FYI: I started to use a project prefix SPC for templates I created see

I also think we should have some kind of documentation standard with standard headers for templates..... and some version number.... with a comment....

Example: Template:SPC_RAÄ that is a map service that supports parish borders in Sweden how it was 1882 

I think question/answers like this should be adressed to the Project Template (don't know how active they are combined with the new draft policy)

Peter, I am one of those testers with the 'extraordinary advantage.' And I have phased my kit on Gedmatch. However, I never use that when I am looking for/at matches. Since I have both of my parent's tests, I always use their kits. That way I already know it is in their line, and they share larger segments (as well as DNA that I didn't get) with any matches. What am I missing, i.e. why would I want to use my phased results as opposed to theirs?  Thanks.
I've wondered the same question, Darlene. My son has phased DNA because both of his parents are tested, but there would be no advantage to matching his DNA test with distant cousins when my DNA test is available.

Hello Darlene,  I  posted this as a query using  "John" at  Jim Bartlett gave his permission to post his reply here: 14 Apr 2016 13:14 (CDT)
Jim Bartlett   Subject: Re: [DNA] Advantage of phased results?

  A lot depends on your objectives. If John is working on his own ancestry, it's better to use his parent's matches - as you note, they\will cover more. But if John is working on his own chromosome map, it's much better to use his phased data, which will sort out which side each Match is on. This breaks a big problem into two smaller problems, but the advantage is much greater than that - once you know which side is which, Triangulation can lay out all the groups on each chromosome quite easily. However, there is then advantage to using the parents'
  Matches still, as often you can determine the Common Ancestor of a Match (particularly close cousins) that a Parent has and you don't have, and from that determine that your ancestor on that segment has to be the other grandparent.
  Using phased data saves a huge amount of time in sorting out which side a Match is on.
  And yes, when one side of a Match is phased, the IBD/IBC vs cM curve shifts to the left (for any given cM, a higher ratio will be IBD). If both Matches are phased the IBD/IBC ratio jumps up even more. It will be great, someday, to amass enough data to draw these three curves from 1cM to 15cM...

  Jim Bartlett -

>>>>>>>>>On 04/14/16, Peter J. Roberts via<> wrote:

  John has phased his results at GEDmatch using both his parents and
  himself.  What are the advantages of using John's matches rather than  his parents' matches?  It seems better to use his parents matches because his parents have DNA that he does not have.  Is there only an  advantage when John is matching someone else who also has phased results?  For example a "3? cM" segment match is real between two phased persons.
  Thank you and sincerely, Peter

Nice website and excellent written

User Story I can see....:

DNA 1: As an user finding a match on Gedmatch I would like to easy find if this user is also part of Wikitree  

Suggested solution 1-1: Search in Wikitree with the gedmatch id....

DNA 2: As an user having my family tree in Wikitree I would like to see on a profile what other DNA tested people are related to this tree and what segments they had a hit on  

Todays solution: We can in Wikitree today see on a profile if other Wikitree users have DNA tested and have a family tree connect to this profile ....

Suggested solution 2-1: Extend todays solution also supporting phased kit (maybe it does or do we need a new type/help pages I assume a phased kit should appear on less number of related profiles...) ==> 

Suggested solution 2-2: That we add support for uploading what segment an two DNA tested users has a match ==> easy extract a list of profiles see list) and also get information 

  1. who connected to this profile has done DNA tests or have phased kits and Gedmatch numbers
  2. if those tested kits has been compared at Gedmatch what segments did they match
Hi Peter, thanks for the information.  I don't think I'll ever work on mapping my chromosomes; I'm too busy mapping both of my parents'! The one thing I do, with having both parents as well as my own DNA tested, is when a person matches both my mom & myself (for example), I look to see if the person is on ancestry & has a tree there.  Because too many people don't have trees attached to their results on Gedmatch.  (Ditto with ancestry & FTDNA...)  I still think the most useful thing we can do and stress to DNA testers is to get together the best 10-generation family tree you can and attach it to your results.  The older we get, the more important this becomes.  Some day we will die, and if we haven't attached our DNA results to a tree 'somwehere' (preferably Wikitree, since it's doing such terrific things with DNA so you can see who else descends from the same person & compare results), then our DNA results become useless, because no one will be able to know our lineage...
In view of the replies is there a difference between DNA phased as the result of one parent tested rather than two?  Logically what doesn't come from one comes from the other. On 23 and me my results are phased as fathers and not fathers. On ged match  I have 2 reference numbers one ending in p1 and the other m1.

Good point, Helen. If you were only able to test one parent, then your phased DNA is the best source of information about the other parent.

If you are only able to test yourself and one parent then you can't phase your DNA.

Gedmatch and 23 and me seem to think that I can. 23and me says ' Results reflect phasing against one parent.'  and mark my matches with p and not p.

On  gedmatch  I used the tool to

 'Generate phased maternal and paternal data files.
You must provide the Child's kit number, and  at least one of the parents' kit numbers.'

On SNPs where you are heterozygous you can of course work out which parent each base came from.For example on SNP rs28680530 my father was AA and I'm AG, therefore the G came from my mother or there is a small probability that it is a de novo mutation . De novo mutations though are very few: 1-2 x10^-8 per base pair per sexual generation ie  60-120 mutations in a diploid per generation (ref Useful Genetics, lecture 2b a brilliant but extremely challenging MOOC by Rosie Redfield . I recommend it and it's good to find all the videos on you tube. )

also see

(Interestingly I actually have far more matches on my fathers side than my mothers but I've only been able to find the actual common ancestor with matches on my maternal side.These were found prior to obtaining my fathers sample so finding that the matches truly linked with my non fathers DNA seemed to confirm  the usefulness of being able to  separate it)



I stand corrected.  Thank you.
I prefer the use of atDNA for autosomal results/tests but I come from the FTDNA side of things... I agree with most of the answers posted; however, it seems the power of using phased results should be suggested for those without rich trees to begin with - and that might include any NPE or surname misspelling.
Has the idea of a template/category for phased DNA been decided? Is it time to revisit this idea?

3 Answers

+8 votes
Best answer

Why not a template? 

Name: DNA_Phased_Gedmatch


A) Easy find people using the template: 

B) If you later find something that better explains what a Phased Autosomal DNA test is you can just add that to the template and all pages are updated ex...
* DNA Explained....

C) If i.e. Gedmatch start supporting direct links ==> you need just to change the template and all people using the template will be updated

D) If you would like to have a Category then the Template can add it

E) If you decide later to change the name of category used then its just updating that template (this is how we did in the SPC project)

by C S G2G6 Pilot (273k points)
selected by Theresa Myers
+8 votes

wouldn't it be enough to indicate the phased results kit numbers on the users profile? It's obviously very useful but I question why everything needs to be put up in categories.

A category is for finding people/user profiles to further extend your family tree. While there is no black and white (this one is rather gray), I think we should have a better solution by having two new fields in the DNA results where we can directly enter the phased results kit number (or actually two new check boxes would be enough as the format is always quite clear).

Difficult to rope Chris into this discussion but I wonder if that wouldn't be a better standard (also in regards to machine readable information, like Magnus is proposing lately).
by Andreas West G2G6 Mach 5 (53.9k points)
I already have a note in my DNA profile of my phased kit numbers.  I'm not sure a category would be worthwhile, but different check boxes seems like a good idea.
+9 votes
PhatDNA  ??
by Pat Davis G2G Crew (490 points)

Related questions

+9 votes
1 answer
+22 votes
2 answers
+6 votes
1 answer
+8 votes
1 answer
+13 votes
6 answers
+13 votes
3 answers
+12 votes
3 answers

WikiTree  ~  About  ~  Help Help  ~  Search Person Search  ~  Surname:

disclaimer - terms - copyright