Cholera is characterized by severe watery diarrhea caused by toxigenic Vibrio cholerae, which colonizes the small intestine and produces an enterotoxin, the cholera toxin (CT).
V. cholerae is classified on the basis of somatic antigens (O) into serovars or serogroups, and there are at least 200 known serogroup. Two serogroups, O1 and O139, have been associated with epidemic disease . Serogroup O1 thought to include all the strains responsible for epidemic and endemic cholera; it has two major serotypes, Ogawa and Inaba. Each of those serotypes can be further divided into two biotypes, classical and El Tor, based on biochemical properties and susceptibility to bacteriophages. Serogroup O139 appears to be a hybrid of O1 strains and non-O1 strains. However, this organism does not produce O1 LPS and lacks at least some of the genetic material necessary for production of O1 antigen .
In Indonesia, a total of 17 episodes of epidemic diarrheal disease were investigated from 1993 to 1999 and were found to be caused by V. cholerae O1 . According to WHO report , there was a sharp increase in the number of cholera cases. A total of 131943 cases, including 2272 deaths, reported from 52 countries. Overall, this represents a 30% increase compared with the number of cases reported in 2004.
In Indonesia edible are often used in street food and are consumed almost every day. Although it is so commonly consumed, it may not be prepared properly. We suspect that it may be a major important concern and we conducted a study on the genetic diversity of V.cholerae isolated from this possible source of contagion.
The initial analysis of Repetitive Extragenic Palindromic (REP) sequences in E. coli showed that this sequence was frequently present in complex clusters of several copies. These clusters are present and transcribed in about 25% of transcription units and may account for as much as 1% of the total genome. The REP element has been shown to be located between genes within an operon or at the end of an operon, and in operons distributed throughout the E. coli genome .
From the analysis of DNA sequence databases, Enterobacterial Repetitive Intergenic Consensus (ERIC) sequence is found to be approximately 126 bp in length. Like the REP sequence, the ERIC sequence repeat includes a conserved inverted repeat  and is located in non-coding transcribed regions of the chromosome, in either orientation with respect to transcription.
ERIC-PCR has been chosen for intraspecies profiling to several bacteria, for instance Bacillus anthracis and Bacillus cereus, Enterobacter sakazakii, Lactobacillus, Listeria monocytogenes, Salmonella enteritidis[11, 12]. According to  ERIC-PCR typing can provide more discriminative DNA patterns of Bacillus anthracis and Bacillus cereus strains. Comparison of ITS profiling, REP- and ERIC-PCR of Salmonella enteritidis showed that ERIC-PCR can give high discriminatory index . On the other hand, ERIC-PCR was able to show species specific band that pulsed field gel electropheresis could not show it . Those comparisons has revealed that ERIC-PCR is a powerful techniques and informative for intraspecies profiling.
Thus, the objectives of this experiment were to obtain information on the genetic diversity of V. cholerae from edible ice samples used in street food using ERIC-PCR, and to compare the effectiveness of REP-PCR and ERIC for analysis genetic diversity of V. cholerae.