Welcome to the COFFEY y-DNA Project. This project is focused on the y-DNA testing and result reporting for males with the Coffey/Coffee (or similar) names, or those with Coffey DNA matches.


GDPR (General Data Protection Regulation): The information here can be seen by the public, and we believe we have the permission of all Coffey Project participants. If any reader sees information he does not want to display, he has a “right to be forgotten”: Click on GDPR box below for info.


NAVIGATION: The following yellow boxes contain hyperlinks. Click on any topic, and a new page should appear. That may lead to more choices. Use your “back arrow” to return to a previous page.


If you haven’t been here before, start with “Introduction”, or “Need Help?” If you’re already tested, and trying to find which group you belong with, start with “Participant Index” below:



Need Help?

Free Advice!

Background Discussions

Major Groups

Coffey Geography

Untested Targets

Reading the Data and Genealogy Files

Data Detail for Tested People

Genealogy Detail for Tested People


Participant Index






ALTERNATIVE NAVIGATION: Once you get used to this, try clicking on “SITE KEY”. That will bring up an overview of the whole system, and you can click directly on any topic without following the path.


MEMO: From time to time there will be blue boxes.  These are links to related topics that have been discussed in historical CCC Newsletters (all available online). They will refer to a specific page, so you may have to scroll down to the page you want. This one is just an example. Give it a try.


First Ever CCC Newsletter - 1981 (See “objective”, page 3)