Thus, the remaining 18 groups of strains produce mutacins that differ from the mutacins sequenced to date.
This phenomenon was described by Dunn et al. ([2012]), who observed similar pairs or groups of strains, but could not find clusters based on geographic origin using array- Comparative Genomic Hybridization (aCGH) for 83 different S. cerevisiae strains.
The sequences from both genes cluster in four major groups, a result that is not fully consistent with the current classification of T. cruzi in two major groups of strains.
This resulted in an almost perfect segregation between the iso1- and iso10-treated groups of strains.
However, to map GR alleles the variation between entire groups of strains (segregated by the genotype at some marker, as in Fig. 1c) must be compared.
A trait's ER can differ between two groups of strains due to a polymorphic factor where one allele buffers environmental variation more effectively than the other.
Phylogenetic analyses of multiple genes, including the mating loci (HMG, TPT, RNA helicase), ITS1-5.8S-ITS2 rDNandRPB2, and LDH genes, identified two distinct groups of strains.
Glycoside hydrolase and N-acetylmannosamine-6-phosphate epimerase genes present within the region in both groups of strains share 50% nucleotide sequence identity.
However, the regulator genes profile of these two groups of strains differed, since rgf locus and rogB gene were associated with CC17 and CC23, respectively.
The identification and precise definition of virulent clones, i.e. groups of strains with a single ancestor that are associated with particular infections, is critical to understand the evolution of pathogenicity from commensalism and for a better control of infections.
A few recent studies that have analyzed tubercle bacilli from India using multiple markers [2], [14], [15] reveal a clear predominance of two important genogroups (TbD1− and TbD1+ groups of strains), confined to North and South India, respectively.
