This project is open to males with any variation of the Coursey or DeCoursey surnames (see below) or to any man believing that he is descended from one of those names. Participants are sought from all parts of the world.

Free and rebated tests are available for participants from certain lineages and places of origin. See the Wanted! page for more information.

Examples of surname variations
Coursey, Corse, Courcey, Courcy, Courci, Course, Corsey, Courson
de Courcy, de Courcey, DeCoursey, DeCourcey, DeCourcy, DeCorsey, DeCourse

Participant Requirements
The region of DNA tested is located on the Y-chromosome, which only males have. It is passed from father to son more or less unchanged, except for random mutations. The tested individual must therefore be a male from an unbroken male (De)Coursey (or surname variant) line, or believe he is descended directly from one.

How to Participate
Males with the (De)Coursey (or variant) surname, or a suspected (De)Coursey paternal line:

Females (and males with a non-(De)Coursey paternal line):


Click HERE to place an order for a DNA test at Family Tree DNA at group pricing.

Purchasing a Testing Kit
The main testing company for this project is Family Tree DNA, of Houston, TX, the World's leading testing company for Surname DNA Projects. All tests include a Y-haplogroup assignment (an indication of deep ancestry). Participants are welcome to use other testing companies if they would rather do so, although we do recommend using FTDNA. Contact the project administrator for more information. The more markers you have tested, the more relevant matches can be made with project members. More markers also allow for the possibility of being able to separate participant groups into more closely related clusters. We therefore strongly recommend buying the largest number of markers that you can afford. We hope that serious researchers test at least 37 markers.

The following are Family Tree DNA's Y-DNA test prices for group members: (See FTDNA's order page for pricing on mtDNA and autosomal tests and combination packages.)

  • The test is a simple cheek swab. The kit will arrive and leave your house by mail. You simply rub the inside of your cheek a number of times with a special scraper, put the kit back into the envelope, and put it in the mail.
  • If you wish to participate, place an order for a DNA test and submit your pedigree. (See the Patriarchs page for instructions.)

  • Project Testing Fund
    Since the high cost of DNA testing can be a major obstacle in participation, the project has a general fund that is used to offer reimbursements of the cost for participants from certain lineages (see the Wanted! page). If you meet the requirements and would like to order a rebated test, contact the project administrator. If you would like to contribute to the fund contact the project administrator. You may either contribute to the general fund or stipulate your own requirements.

    Things to consider before having a DNA-test
    The DNA information is to be used in conjunction with historical and traditional research. If a DNA profile does not match traditional genealogy, a hypothesized relationship may be incorrect. At other times DNA results may point to an unknown adoption in the family, or some other so-called non-paternity event.

    Privacy and Other Concerns
    The section tested is a small piece of "junk-DNA" on the Y-chromosome which does not reveal any medical or other information about the tested individual. Also, it is not unique to a certain individual but is shared by all male direct line descendants of an earliest known male ancestor (this could be hundreds of people living today). If privacy issues are a concern it is possible to ensure that a participant's name is not associated with the test results.

    Here are some webpages that address common DNA-testing concerns:


    What do I do if I have questions?

    1. Please read the Freqently Asked Questions at World Families Network.

    2. If you still have questions you are welcome to contact the Project Administrator listed below.