Polymorphism ratio sequencing labeling and reaction tube pooling scheme. Insets present the four-color labeling scheme for bases A/C and G/T in sample and reference sequences. (A) A and C extension products from the sample template are respectively labeled with R110 (λ_max 525 nm) and ET-TAMRA (λ_max 580 nm). Similarly, A and C extension products from the reference template are labeled with ET-R6G (λ_max 555 nm) and ET-ROX (λ_max 605 nm). Products from the four reactions are combined and analyzed in a single lane. (B) G and T extension products from sample template are labeled with R110 and ET-TAMRA, and reference template G and T extension products are labeled with ET-R6G and ET-ROX, respectively. The baseline signal intensity of the four channels has been offset to show coincident peaks more clearly.