Detection and sequence analysis of DNA polymerase and major envelope protein genes in koi herpesviruses derived from Cyprinus carpio in Gunma prefecture, Japan.
Koi herpesvirus (KHV), which is believed to be an emerging virus, causes fatal diseases in carps. Since the 1990s, the presence of KHV has been confirmed in several countries. In Japan, from 2003 to 2004, large outbreaks of KHV infection in farmed carps resulted in the death of numerous fishes. From April to May 2004, we collected 43 dead or dying carps exhibiting typical symptoms of KHV infection in Gunma prefecture. To conduct a molecular epidemiologic study of KHV in our prefecture, we amplified DNA polymerase and the major envelope protein genes of KHV derived from carp gills using newly designed primers. We also performed sequence analysis of both genes of KHV. Sensitivity of our PCR method for amplification of DNA polymerase and the major envelope protein genes of KHV was 3 x 10(2) (100 fg) and 3 x 10(3) (1000 fg) copies of KHV genome, respectively. We detected both DNA polymerase and major envelope protein genes in 37 of 43 carps (86%). No mutation was found in both the genes sequenced from 11 strains, which included two foreign strains and one domestic strain. The results suggested that KHV strains derived from carps in our prefecture were closely related genetically to the other KHV strains.
Ishioka
Taisei
T
Gunma Prefectural Institute of Public Health and Environmental Sciences, 378 Kamioki, Maebashi, Gunma 371-0052, Japan.
Yoshizumi
Masakazu
M
Izumi
Shotaro
S
Suzuki
Kyuma
K
Suzuki
Hiroko
H
Kozawa
Kunihisa
K
Arai
Masanao
M
Nobusawa
Kunihiro
K
Morita
Yukio
Y
Kato
Masahiko
M
Hoshino
Toshie
T
Iida
Takaji
T
Kosuge
Kanae
K
Kimura
Hirokazu
H
D000818:Animals; D001483:Base Sequence; D002347:Carps / Q000821:virology*; D004279:DNA, Viral / Q000032:analysis; D004259:DNA-Directed DNA Polymerase / Q000235:genetics*; D004196:Disease Outbreaks / Q000662:veterinary; D005393:Fish Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000821:virology*; D005784:Gene Amplification; D005880:Gills / Q000821:virology; D006564:Herpesviridae / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D006566:Herpesviridae Infections / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D007564:Japan / Q000453:epidemiology; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods / Q000662:veterinary; D012680:Sensitivity and Specificity; D014759:Viral Envelope Proteins / Q000235:genetics*
D004279:DNA, Viral; D014759:Viral Envelope Proteins; D004259:DNA-Directed DNA Polymerase