A sample excavated at the Houtaomuga site in the Yonghe neighborhood of Honggangzi Township, Da'an, Jilin, China dating back to 7430–7320 years ago (Phase II of the Early Neolithic) has been found to belong to Y-DNA haplogroup N and mtDNA haplogroup B4c1a2. This sample is autosomally identical with the Neolithic Amur River Basin populations, of which Nivkh people are the closest modern representative. As the paper detected this ancestry in terminal Pleistocene USR1 specimen in Alaska, it is therefore, postulated that there was gene flow from Amur to America of a population belonging to a hypothetical Chukotko-Kamchatkan–Nivkh linguistic family.[65]