comparative gene sequencing of ibosomal RNA Phyogenetic tree?

Answer 1

I'm not sure of the question, but often Ribosomal RNA or even DNA is used for comparative gene sequencing because the area is conserved enough to get consistent PCR products and thus successful sequencing, but enough differences between species to compare the number of genetic differences in the region and then map the differences into branch lengths to create a phylogenetic tree.

The utility of the phylogenetic tree, or the perceived accuracy of it is directly related to the region used to compare DNA sequences, and the ribosomal region is generally considered the best for species separation. For strain separation in microbes for instance, it wouldn't be useful because the different strains of the same species would have no genetic differences in this region.