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lukaszM
06-01-2017, 08:22 AM
It's new alghoritm.

https://genesis.gedmatch.com/login1.php


GEDmatch Genesis is a peek at things to come for GEDmatch. It provides two things:

Ability to accept uploads from testing companies with formats and SNP sets not compatible with the current main GEDmatch database.

A new comparison algorithm that we believe will provide better accuracy, and more flexibility. More info: The Genesis Algorithm

During this initial deployment, the GEDmatch Genesis database will be separate from the main GEDmatch database, and comparisons for one will not show entries made in the other. Eventually, the 2 databases will be merged, and results will include entries from both. Likewise, the benefits of the Genesis comparison algorithm will eventually become available to all GEDmatch users.

The initial offering of Genesis applications will be limited to autosomal DNA matches. That too will be expanded as we move forward in our effort to convert existing GEDmatch software to the new algorithm.

We hope you find this transition to GEDmatch Genesis useful.



The Genesis Algorithm

For several years, GEDmatch has provided genetic genealogists, both beginners and experts, the ability to search for matches among kits in their database without regard to vendor. Also, GEDmatch has provided a rich suite of analysis programs allowing users to dig deeply into the genetic details of their matches, enhance the reports from their vendors, and even pursue their own original research ideas. Our algorithms are evolving to extract the most trustworthy and meaningful matching information possible using the markers common to pairs of kits even though sometimes limited.


Unfortunately, all too often, kits appear to share a DNA segment purely by chance. To combat this confusing phenomenon, we recently have developed a reliability measure that allows users to assess the quality of a matching segment in an intuitively appealing fashion. We also use the measure to guide our matching algorithms as they wring the greatest amount of useful information possible from the markers common to pairs of kits.


If we could assume that marker characteristics were uniform in all regions within chromosomes, we could use a "one size fits all" requirement for matching segments as is sometimes done. Unfortunately, the relevant characteristics vary widely. Some long segments with few markers may be accidental matches. Some marker rich short segments are often discarded although they are profoundly non-random.


Using the characteristics of each and every marker in a segment, we compute the expected number of purely chance matches to it to be found in the database. That number is then used to classify the segment into one of several levels reflecting the likelihood that the random matches may overwhelm the real ones. When a user executes a one-to-many search or a one-to-one comparison specifying a minimum segment length, the display can then include an estimate of validity for each segment found.


One can assume those segments designated to be valid are the result of a DNA inheritance process rather than mere chance. Questions may still remain about how far back shared DNA originates, but a confounding factor has been removed.

lukaszM
06-01-2017, 08:55 AM
For now I found there match with 43 cM, much bigger then in normal Gedmatch (biggest was 29 cM).

AntG
06-01-2017, 05:23 PM
For now I found there match with 43 cM, much bigger then in normal Gedmatch (biggest was 29 cM).

I've just tried it. I'm 8th on your list... but 7.4 Gen away!...

dnoone
06-01-2017, 06:09 PM
Trying to upload the vcf from dna.land but failing so far

firemonkey
06-01-2017, 06:35 PM
I get quite a few with the email of Tim Janzen. Practically all 7.0 gen or above.

Angoliga
06-01-2017, 07:01 PM
What characterizes a rich marker segment? Would that in anyway translate into the amount of SNPs on a given segment?



I occasionally find low matches (<7cM) with rich SNP segments (+1000 SNPs), more often than not these distant matches appear related to more immediate family members than segments under 700SNPs.

Vadim Verenich
06-03-2017, 02:30 PM
For now I found there match with 43 cM, much bigger then in normal Gedmatch (biggest was 29 cM).

That's because they have imputed the missing snps using Michigan/Sanger Imputation server, you'll get segments longer than they actually are. I am also expecting serious bias towards the increasing number of matches with people from British Isles, because their reference set includes thousands of autosomal haplotypes from UK 1958 DNA cohort.

In short,

A British person vis a vis other West European/British person - the quality of match significantly imporves
A british person vis a vis other East Europeah person - the quality of match will still the same or decreases

lukaszM
06-07-2017, 06:34 PM
That's because they have imputed the missing snps using Michigan/Sanger Imputation server, you'll get segments longer than they actually are. I am also expecting serious bias towards the increasing number of matches with people from British Isles, because their reference set includes thousands of autosomal haplotypes from UK 1958 DNA cohort.

In short,

A British person vis a vis other West European/British person - the quality of match significantly imporves
A british person vis a vis other East Europeah person - the quality of match will still the same or decreases

Yes, I have this match with some guy from Gedmatch team. I mailed him and he responsed this match is:


About the close 'Exome' matches

Are you puzzled by the new, very close, match you are seeing with somebody. Does it have "Exome" in the name? Even if it does not say "Exome", there are a few "Exome" kits on Genesis. Exome kits are different than the "genealogy" kits we are used to dealing with. The exome regions of the chromosome have much less difference from one individual to the next. Because of that, they appear as close matches to more people.

We apologize for the "false match". We plan to provide some means of differentiating these "exome matches" from the real thing, but it will take a while to get it in place.

cvolt
06-30-2017, 10:54 PM
Most of my matches on there are from Russia or Spain, so that's where they were hiding :P

Peter Towey
07-12-2017, 01:29 PM
Is there a crib to the data in the new Genesis results? eg what does "C" mean? Also "Overlap" seems to be roughly the same as the SNPs used for the comparison.

Tomenable
08-06-2017, 01:25 AM
Is this already working well or still in testing phases?

Tanchik
07-18-2020, 03:48 PM
Yes. It worth one month is enough