Welcome to the Trethewey worldwide DNA project which was set up in July 2012. The DNA Project is linked to the Trethewy One-Name Study, which is registered with the Guild of One-Name Studies in the UK. Other variants of the surname include Trethewy, Tretheway, Trethewie and Trethaway.

This project is aimed at anyone who is interested in trying to trace their Trethewey heritage. The surname originated in Cornwall, England, but has spread worldwide. 

Sharing information obtained from genealogical records, such as wills, parish, census and family records, can help break down brick walls in research when combined  with DNA testing. 

The Trethewey Project uses the Y-DNA test, which tells you about your direct male line, that is, your father, his father, etc. You must be a male to take this test, with one of the surnames shown. If you are female, you will need to ask your brother, father, uncle or cousin to take part. Please order a Y-DNA test for a minimum of 37 markers.

The project is also collecting Family Finder results from both males and females with these surnames anywhere in their tree within the last seven generations.

The privacy of project members is respected and the volunteer project administrators adhere to the Group Administrator Guidelines for Family Tree DNA Projects and the ISOGG Project Administrator Guidelines.