An insertion in the unedited region of the Sylvio X10 Cyb gene. A) Portion of the Cyb nucleotide alignment from T. cruzi strains Sylvio X10, CL Brener, and Esmeraldo. The Sylvio X10 Cyb gene contains an insertion ('i' under the alignment) at position 817, disrupting the reading frame and resulting in an early stop codon. Positions of single nucleotide polymorphisms (SNPs) are indicated by 's' above the alignment; the distribution of SNPs is compiled in Table 3. B) The predicted Cyb amino acid alignment based on the predicted edited sequence in T. cruzi strains Sylvio X10, CL Brener and Esmeraldo. The T insertion present in position 817 causes an early stop codon (#) at position 284. Positions in the alignment with '*' below are identical; '.' indicates a conservative change; a blank represents a non-conservative change or three different amino acids. C) Deletion of Sylvio X10 817 insertion restores the full-length reading frame; the relevant portion of the alignment is shown.