Resistance may be disseminated through clonal expansion of drug-resistant strains or through horizontal transfer of genetic elements coding for resistance determinants.
enterica suggests that clonal expansion may also play a role in dissemination of drug resistance.
Definitions of Horizontal Gene Transfer and Clonal Expansion
Evidence for Clonal Expansion of Integron-mediated MDR in S.
This result is consistent with the hypothesis that a common ancestor has undergone clonal expansion in a number of areas.
Therefore, these isolates are all closely related, and their integrons may represent an instance of clonal expansion.
Although the class 1 integron dfrA12/orfF/aadA2 appears to have been circulated through horizontal gene transfer, this integron has also spread through clonal expansion of nontyphoidal S.
Integrons found in this collection were diverse in size, gene cassette combination and distribution, and presented evidence for roles of clonal expansion and horizontal gene transfer.
In addition, this study focused on the relative contributions of clonal expansion and horizontal gene transfer to the dissemination of class 1 integron borne genes coding for antimicrobial drug resistance, which has not previously been well explored.
Thus, single clonal expansion of ST320, related to a multidrug-resistant internationally prevalent clone, [Taiwan.
Thus, our finding of a clonal expansion of ST320 among serotype 19A strains may be an overstatement.