Arch Virol (2006) 151: 2503–2509
The detection of human sapoviruses with universal
and genogroup-speciﬁc primers
, Y. Yamashita
, M. Oseto
, and K. Shinozaki
Division of Virology, Chiba Prefectural Institute of Public Health, Chiba, Japan
Microbiology Division, Ehime Prefecture Institute of Public Health and Environmental
Science, Ehime, Japan
Received May 19, 2006; accepted June 8, 2006
Published online July 19, 2006
Summary. Sapovirus (SV) causes gastroenteritis in humans and comprises genet-
ically divergent viruses. A nested reverse transcription-polymerase chain reaction
(RT-PCR) targeting the capsid-protein-coding region was developed using uni-
versal and genogroup-speciﬁc primer sets. The universal primers were capable of
detecting human SV genogroups I, II, IV and V. Genetic analysis of the ampliﬁed
products enabled us to phylogenetically determine the genotypes of the viruses.
In addition, genogroup-speciﬁc primers that ampliﬁed different lengths of the
amplicon depending on the genogroup were developed. These genogroup-speciﬁc
primers were also used as inner primers for the nested PCR. These two simple RT-
PCR methods are powerful tools for both detection and epidemiological studies
of human SV.
Sapovirus (SV) is a member of the genus Sapovirus in the family Caliciviridae
and comprises genetically divergent strains. SV causes gastroenteritis in humans
and pigs [1, 3]. SV strains are currently divided into ﬁve genogroups (GI–GV),
of which GI, GII, GIV, and GV strains infect humans, and GIII strains infect pigs
. The SV genome contains two or three open reading frames (ORFs) . ORF1
encodes a polyprotein for non-structural and capsid proteins. ORF2 encodes a
small basic protein. A putative ORF (ORF3) that overlaps with ORF1 is found in
GI, GIV, and GV strains, but not in GII and GIII strains [3, 6, 7, 17]. Human SV
cannot be cultivated in any cell line, and also cannot be propagated using animals.
Several methods using reverse transcription-polymerase chain reaction (RT-
PCR) have been previously reported for the detection of human SV [5, 10, 14, 19].