As far as I can see, the only link between Marsh Arabs and
Sumerians presented in this paper comes from dating Y-STR
variation of their major J1-Page08 group using the evolutionary
mutation rate, with a divergence time of 4.5 +/- 2.6 ky. Even if
that mutation rate was correct (it is not) and the assumptions
on which the confidence interval are based were exhaustive (they
are not), we still have +/- 2.6 ky leeway to deal with, which
spans not only the Sumerians but plenty more besides. Not to
mention that the evolutionary mutation rate is wrongly applied
to every case under the sun, and that Y-STR based age estimation
in general has been conclusively shown to be a rather futile
exercise. Nonetheless, the paper does have value in
demonstrating the paucity of J2 and R1 in the Marsh Arabs
compared to the more cosmopolitan general Iraqi population:
Rather than "Sumerian", it seems that the Marsh Arabs have
rather preserved a more pristine Semitic patrilineal gene pool
compared to the cosmopolitan Iraqi samples tha