We would like to invite all those whose origins come from the South-Eastern side of Baltic Sea, including those from Baltic tribes' origin and surrounds from Germany to Finland, Lithuania to Belarus, along with Estonia,Latvia, Russia and Ukraine. Also all close matching persons are cordially invited to the Baltic Sea DNA Project, regardless of whether they match Y-DNA or mtDNA lines. We are especially interested in N-L1025 and I-L621 subclades and to that end and we have achieved participation in the BigY testing program of over 100 of the Baltic Sea DNA Project members! Also we are trying to identify subclades in mtDNA based on Full Mitochondrial Sequence only. The Baltic Sea DNA Project is a linear project - Y-DNA and mtDNA. Of course, people interested in autosomal tests (Family Finder) also participate in Baltic Sea DNA Project. But they are the "dark matter" of the Project if they also do not have Y-DNA and / or mtDNA testing. So our invitation is under condition in further testing one of this two lines: paternal or/and maternal.