The Complete Guide to Gedmatch & How to Use it for DNA Genealogy

Gedmatch is a free, public service that lets you do raw DNA comparisons with others who have tested at Ancestry, 23andMe, or FamilyTreeDNA.

· 4 min read
How to use Gedmatch?
Photo by Andrew Neel / Unsplash

Gedmatch is an online DNA matching service which is popular among many genetic genealogists. But did you know how to upload your DNA data and use Gedmatch to get your ethnicity estimates? The website compares SNPs from your autosomal DNA test to others like you who have uploaded their DNA data. Depending on the number of shared DNA segments, it then provides a % match with your potential DNA matches.

Additionally, all contact information (like name and email address) is visible to your matches so you can be contacted. This has helped over 10,000 adoptees to find their biological parents.

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Gedmatch logo

Gedmatch gained significant visibility after it was used by the FBI to track down the suspect in the Golden State Killer case in California. It was founded by Curtis Rogers and John Olson in the year 2010 and the main purpose was to connect “amateur and professional researchers and genealogists”, including adoptees searching for birth parents.

Below are 7+ insights that I have put together that will show you how to use Gedmatch.

What is a Genetic Triangulation Match?

A genetic triangulation match is a tool that helps people find their biological relatives. It works by comparing autosomal DNA to other people in the database who are not related. This process is called triangulation.

The process of triangulation uses family trees and genealogical records to find potential relatives, then matches them using autosomal DNA. The goal of this process is to find as many relatives as possible from both sides of the family tree, which can help identify unknown relatives.

What is Gedmatch Genesis?

Gedmatch’s Genesis is the name of the new algorithm that is used to identify matches from the SNPs (variations) that you carry in your DNA. With the new algorithm, you can use data from multiple DNA testing kits and perform one-to-many, many-to-many matches, chromosome comparison and user lookups.

Is Gedmatch free?

Gedmatch Genesis is free for use. They also have a paid version named “Tier 1”. It will cost you $10 per month. With the paid version you get access to some fancy tools such as triangulation, matching segment search and a customised comparison system. You may want to check out these other free tools that can calculate ancestry proportions.

Who owns Gedmatch?

Verogen Inc does.

Before you move forward with Gedmatch, it is essential to know that it was acquired by Verogen in Dec 2019. Verogen is a forensics company that helps government agencies, labs and individuals in solving crimes through DNA sequencing.

Is Gedmatch safe?

Overall it is safe to use. However, I recommend you read about some of these events that had taken place over the last couple of years.

Gedmatch hacked

Only July 22, 2020, Verogen confirmed that the Gedmatch website was hacked. It is still unclear if the Gedmatch database was hacked. Their website was down for almost a week after the hack. Verogen issued a statement that user data including DNA or login (password) related information was NOT compromised. Verogen has taken necessary precautions to ensure that data is kept safe and secure. However, please exercise necessary precautions while uploading data to any third-party website.

Opt-in privacy policy

In 2019, Gedmatch introduced an opt-in policy. You are presented with the opt-in/opt-out option on the sign-up and login page. During sign-up if you decide to opt-in, you are permitting them to share your data with law enforcement agencies when presented with a warrant. I am still not sure what purpose this serves because, despite this policy, they were forced to share all DNA data in 2019 when the Florida law enforcement agency issued a warrant to do so.

What happened to Gedmatch?

Nothing really. The website still exists. They probably have better security measures after the hack in 2020.

Gedmatch has been around for ten years now and has helped various law and enforcement agencies in identifying suspects using their DNA match algorithm. While it has earned its credibility over the years, the acquisition (Dec 2019) by Verogen is something that you should keep in mind. Verogen “controls” your data and your data can be used for any forensic search.

Does Gedmatch accept raw DNA data from AncestryDNA or a GEDCOM file with DNA relatives information?

Gedmatch accepts data from various DNA testing companies like Ancestry, 23andme, Family Tree DNA, MyHeritage and more. Gedmatch also lets you upload Gedcom files.

You can also convert your VCF data into 23andMe format and upload your data for calculation. There are many VCF file converters available online that can perform this conversion.

How to use Gedmatch in your genetic genealogy research to find ancestors, relatives and distant cousins?

Gedmatch is an outcome of the work done by two volunteers named Curtis and John, who wanted to help genealogy enthusiasts and adoptees find their biological parents. As a result, the website is pretty challenging to use. The UI design is at least a couple of decades old. Additionally, you have to be an expert in genealogy to navigate through complex terminology.

There are plenty of nice explainer videos on Youtube that show you how to use Gedmatch. These videos also explain what Admixture model to use so you can comprehend your DNA test results. I plan to write an in-depth article on the various admixture models (such as MDLP, Dodecad, Harappa etc.) used by Gedmatch. So you might want to check in a couple of weeks for more info on the models. In the meantime, I recommend the following two videos for an in-depth explanation of how to use the Gedmatch tool and interpret results from it.

Other Frequently Asked Questions

What is admixture?

Admixture in genetics means the presence of matching segment(s) of DNA measured in centimorgans (cM) from another distant population in your genome. Several published admixture-based models are used by the Gedmatch tool to discover your matches to track ancestry and heritage.

What is a VCF file format?

Several file formats are available when it comes to storing DNA information. VCF file format is a universal format that is used by researchers and academicians. Companies like 23andMe, FTDNA and Ancestry have their own raw data file formats. Many online tools can be used to convert file formats interchangeably.

What is a Gedmatch kit number?

This ID is different from a DNA kit number that you receive from your testing company. Gedmatch assigns a unique kit numbers for your DNA profile. Please keep this kit number handy as you will be using this throughout the website to find your matches and also to choose various admixture calculators on Gedmatch.