What can I do if the direct family lines in my family have died out ? Y chromosome DNA testing is the most accurate means of determining ancestral lines. There are no more males with a direct line to test.
This chromosome is passed on from father to son generation to generation like a DNA fingerprint. It is accurate back 350 years or more. My grandfather had two daughters, no sons ,and he died in 1927. Don't wait too long as I did to get a cheek swab of your male family member .