This project is open to all confirmed or potential members of clade R1a-S18681, a subclade of a very large Central-Eastern European branch R1a-Z280. We encourage our members to test for 12 or 37 STR-markers which in most cases should be enough to predict the S18681 membership. For more precise classification within clade S18681 we suggest ordering the most informative Y-DNA tests like Big Y-700 or R1a-Z280 Pack (see overlap "Background") Like us on Facebook: https://www.facebook.com/R1aS18681/ See our map with all subclades under R1a-S18681: https://www.google.com/maps/d/u/0/viewer?hl=pl&ll=53.61874839999995%2C23.447760399999975&z=8&fbclid=IwAR0cvKuxl2r6y5abW8cncLtfj7BinXd8MWjUVFmOeqJx0bbLWfpS8fedpLc&mid=1Wev1XRrmyzQl5v12SRiIp8hmqK8 Admin of R1a-S18681 Project: Łukasz Maurycy Stanaszek, Ph. D. Head of Anthropological Laboratory, State Archaeological Museum, Warsaw (Poland); belongs to R1a-S18681 (subclade YP1363>BY24952>BY50754).