Of course, all the influential people Icke labels as part of the Illuminati (another word for Icke's "lizards") are very distantly related, as are most of the members of his audience. Their relationships just haven't been documented yet. Almost everyone in Europe and most every European American can conceivably trace his or her ancestry back to Charlemagne, but that doesn't mean the black helicopters are circling.
Most of us just don't know much about our ancestry beyond our great great grandparents. The number of ancestors one has compounds exponentially each generation: 2 parents, 4 grandparents, 8 great grandparents, 16 great great grandparents, 32 great great great grandparents, and so on . . . Surely presidents, kings and queens, inventors, famous authors, and prime ministers, occur somewhere on every one's family tree, as do outlaws and the infamous.