I agree my friend. It sounds like you are familiar with Fritz Springmeir's book "The top 13 bloodlines of the illuminati" If you are not I highly recommend reading it. He talks about the methods of hiding geneologies.
Even if you wanted to take a blood test they are very aware and protective of keeping geneologies secret.
One of the Collins family members that wasnt too hard to find was tom hanks. Tom Hanks came from the Todd side of the Abraham Lincoln wife family, Collins family members are known to have changed their last name to Collins between the 1800's or 1900's Here is the link to the pdf of the book.

http://www.google.com/url?sa=t&rct=j&q=the%20top%201...