Ancestry of Meg Whitman

Steve Sailer mentions that Jacob Berkman includes Meg Whitman in a list of Forbes 400 Jews ("At least 139 of the Forbes 400 are Jewish"). Google also turns up several previous instances of Jews listing Whitman as a Jew. I find this bizarre. Whitman is Presbyterian, has no Jewish ancestry, and doesn't look remotely Jewish. Her husband's parents are Presbyterian Southerners.

Edit: Removed ahnentafel for Meg Whitman. Someone has already put up a more complete listing of Whitman's ancestors here.