Strategy used to design TY-R, the reverse primer for the serotype Typhi-specific PCR assay.

The DR sequence upstream from EntB0/EntB0var1 is indicated in black letters. The spacers EntB0 and EntB0var1 are indicated in blue letters. The nucleotides belonging to the template for primer TY-R are represented by letters of larger size. The sequence of TY-R is indicated in red, with the deliberate mismatch in green. Mismatch positions between TY-R and the templates of serotypes Emek (EntB0) and Enteritidis (EntB0var1) are underlined.