Electropherogram of SNP markers for polymorphisms between B. nivea var. tenacissima and B. nivea var. nivea. The primer-extension reactions were performed by SNapshot with primers SNP-S62-a and SNP-S62-b, respectively. Polymorphisms between B. nivea var. tenacissima and B. nivea var. nivea are demonstrated by peaks with different colors (A = green, C = black and G = blue) at known locations. Orange peaks indicate positions of the LIS internal size standard (GeneScanTM-120).