Unfortunately, the only way to find Kehoe relations through DNA is to test a male Kehoe relation. Even a distant male cousin of your Kehoe line would do. The male line in DNA testing is called the "Y" line and the female line is the "X" line. Men carry both the Y line and the X line, while women carry only the X line. You could have your X line tested by taking an mtDNA test, but it would only show you the direct line that goes from your mother to her mother to her mother to her mother and so on. It would give you no information on any of your male lines. There is also an "autosomal" test you can take, which tests all of your DNA and matches you up to geographical areas. These test often are very accurate to people who are not of very mixed ancestry. I am 75% Irish, Scots/Irish and 25% French-Canadian, and my top two geographical matches are the north of Ireland and Glasgow, Scotland. Toulouse, France came in fifth.