http://www.pnas.org/content/97/12/6769/F2.expansion is one genetic study there are multiple out there if you look. The upshot is that the genetics show that Palestinian Arabs and Jews are descended from the same core population, which meshes with historic accounts that the Palestinians were first converted from Judaism to Christianity, and then from Christianity to Islam by successive empires that overtook their areas.
You should love this data because it implies that Palestinian Arabs are equally the modern descendants of the original Jewish inhabitants and therefore have equal claim on the land--they are not interlopers who moved into the area over time, they are converts from the original population. That's why this data makes Zionists uncomfortable. It tends to make Palestinians uncomfortable as well because their hatred of Jews doesn't mesh well with their own Jewish ancestry.
