Figure 1. A schematic representation of diagnostic RFLPs (or variable positions sequenced) used to assort mtDNA haplotypes. Phylogenetic relationships of all the haplogroups detected in the glaucoma cohort studied are graphically represented. Diagnostic positions, detected by RFLP or sequencing, are depicted on the branches relating haplogroups. Positive signs (+) indicate restriction-site gains and negative signs (-) indicate restriction-site losses.