Heritage Album

how can current DNA tests tell me my ancestors who were never tested?

Some research firms claim that they can tell my family history lines by DNA test which I submit. My ancestors were never tested. Are such claims valid. If I submit a test swab, without additional information,can they tell my family tree?

Public Comments

1. it's bull
2. Different races have pre-cursors or markers in there DNA.With this they can match you to them.It won't tell you who your relatives are,but will tell you what races course through your veins.Dr. Spence Wells,Geneticist has proved we are all related as humans.There is only 1 species of human.The only reason why we look different is because the human body adapts to its environment.Under the skin we all are the same.
3. They can compare your DNA to that of a known descendent of a historical figure. For example, if your DNA matches up to that of a known descendent of George Washington, you can safely say that you're descended from Washington yourself. They can also compare your DNA to intact DNA samples of historical figures. This doesn't mean they submitted themselves to a test though; all scientists need is a hair or fingernail, etc. For example, scientists have a sample of Ghengis Khan's DNA, so it's possible to determine whether or not you're related to him via DNA sample. A DNA sample probably won't get your a full family tree though unless there's someone in there known to history. Your best bet for this would be talking to relatives, looking through public records and family bibles.
4. DNA samples were taken from people in a specific region. The results were compared for commonalities to determine the basic DNA from that particular region of the world, i.e., Northern European, Mediterranean, Middle Eastern, South Asian, African, Native American, East Asian. These basic ancestry tests (paternal and maternal lines) are reliable, but vague. Some companies claim to be able to narrow the results even further, e.g., Chinese, Korean, Japanese, etc. But, these are still controversial as there may not be enough genetic diversity to make such finite distinctions. This will eventually change with more knowledge of specific sequences of DNA, and more samples for comparison. For now, however, such tests are likely a waste of money.