The project is the SSRs data of 12 populations in China and North America. The Chinese populations include Panjin (PJ), Tianjin (TJ), Tangshan (TS), Lianyungang (LYG), Yancheng (YC), Zhoushan (ZS), Putian (PT), Zhangzhou (ZZ), and Zhanjiang (ZJ) and the North American populations include Commonwealth of Virginia (VI), Lange Eylandt (LE), and Rhode Island (RL). The markers involved in this data are 7, including RUMM017, RUMM018, RUMM020, RUMM021, RUMM032, RUMM034, and RUMM047.

SSR's primer selection SSR site primers RUMM017, RUMM018, RUMM020, RUMM021, RUMM032, RUMM034, and RUMM047 were created by Wang et al.[45], and all forward primers had a cac sequence tag (5'- cacgacgttgtaaaacgac -3') and 6-carboxyfluorescein (FAM) added to the 5' end. The PCR products were then delivered to Tsingke Biotechnology Co., Ltd., and electrophoresis was performed using a 3730xl DNA analyzer. Based on the known traits (size range, repeating motifs) of a single microsatellite region, the microsatellites included in the assemblage are chosen. Reaction system: 25 ml of 2X Accurate Taq Master Mix, 15 ml of template DNA and RNase-free water, 1 ml of forward primer, and 1 ml of reverse primer. Reaction conditions: predenaturation at 95 °C for 15 min; denaturation at 94 °C for 30 s; annealing for 1 min 30 s; extension at 72 °C for 1 min 30 s (a total of 35 cycles); and extension at 72 °C for 10 min.