To determine the distribution of rotavirus strain genotypes in South Korea, rotavirus-positive stool specimens were collected from July 2002 through June 2003 at 8 hospitals in the Korean Rotavirus Strain Surveillance Network, and they were genotyped by means of reverse-transcription polymerase chain reaction. The globally uncommon G4P[6] type was the most prevalent type identified among strains (27% of strains), the newly emerging G9P[8] strain accounted for 11% of strains, and the globally common genotypes (i.e., G1P[8], G2P[4], G3P[8], and G4P[8]) constituted 55% of the strains characterized. Ninety percent of G4P[6] strains were detected in specimens obtained from neonates. Common genotypes were responsible for the rotavirus epidemic that began in January 2003 and ended in May 2003; however, an early peak in infections with the G4P[6] strain occurred from August through October 2002, and infections with this strain were detected throughout the remaining study period. G4P[6] strains were most commonly identified at 6 urban health care centers, but they were absent from 2 rural health care centers. The newly emerging strain G9P[8] represented a relatively greater proportion of strains identified at a hospital in the central region of Korea and at 2 hospitals in the southern region. The identification of novel rotavirus genotypes in this laboratory-based surveillance study underscores the importance to public health of continued strain surveillance among children for whom prevention of rotavirus infection by vaccination might be considered.

Background and ObjectivesRecent studies indicate that in response to vasoconstrictor stimuli, the small GTPase RhoA and its down-stream effector, Rho-associated kinase 2 (ROCK)/Rho-kinase, are associated with hypercontraction of the vascular smooth muscle of coronary arteries through augmentation of myosin light chain phosphorylation and Ca2+ sensitization. Expression of ROCK/Rho-kinase mRNA was significantly increased and up-regulated in the spastic coronary artery in a porcine model, and a specific inhibitor of ROCK/Rho-kinase inhibited coronary artery spasm in humans. We therefore explored the role of ROCK2 polymorphisms in the pathogenesis of vasospastic angina (VA).Subjects and MethodsWe studied 106 patients with VA who exhibited spontaneous or provoked coronary spasm during coronary angiography and compared the prevalence of ROCK2 polymorphisms between this group of patients with VA and controls whose angiograms were normal, and in whom the ergonovine test did not cause spasm (n=107). Five single nucleotide polymorphisms (SNPs) of the ROCK2 gene were selected. SNPs were genotyped by high-resolution melting. Linkage disequilibrium and haplotype analyses were performed using the SHEsis program.ResultsThe prevalence of genotypes of the 5 interesting SNPs in patients with VA was not different from that in the control group. In haplotype analysis, the haplotype G-T-C-T-G (in order of rs978906, rs2271621, rs2230774, rs1515210, and rs3771106) was significantly associated with a decreased risk of VA (p=0.007).ConclusionThe haplotype G-T-C-T-G in the ROCK2 gene had a protective effect against VA, suggesting the involvement of ROCK2 in VA pathogenesis.