Arch Virol (2004) 149: 261–273
Unambiguous identiﬁcation of JC polyomavirus strains
transmitted from parents to children
H.-Y. Zheng, T. Kitamura, T. Takasaka, Q. Chen, and Y. Yogo
Department of Urology, Faculty of Medicine, The University of Tokyo,
Received May 9, 2003; accepted August 20, 2003
Published online October 30, 2003
Summary. JC polyomavirus (JCV), the etiological agent of progressive multifocal
leukoencephalopathy, is ubiquitous in humans, infecting children asymptomati-
cally, then persisting in renal tissue. It has been proposed that JCV is transmitted
mainly from parents to children through long-term cohabitation. The objective of
this study was to further elucidate the mode of JCV transmission. In 5 families, we
selected parent/child pairs between whom JCV was probably transmitted (judged
on the basis of the identity of a 610-bp JCV DNA sequence between the parent
and child). We established 5 to 9 complete JCV DNA clones from the urine of
each parent or child. The complete sequences of these clones were determined
and compared in each family. Nucleotide substitutions were detected in 4 parents
and 1 child, and sequence rearrangements (deletions or duplications) were found
in 2 parents and 2 children. Phylogenetic comparison of the detected sequences
indicated that the diversity of JCV DNA sequences was generated in each family
(i.e. not caused by multiple infection). We found that in 4 of the 5 families, a
sequence detected in the parent was completely identical to one in the child. These
ﬁndings provided further support for the proposed mode of JCV transmission, i.e.
parent-to-child transmission during cohabitation.
JC polyomavirus (JCV) is the causative agent of a fatal demyelinating disease in
the central nervous system, known as progressive multifocal leukoencephalopathy
(PML) [26, 29]. However, this virus is ubiquitous in the human population.
Primary infection usually occurs asymptomatically during childhood [30, 40].
JCV persists in the kidney of most adults, who excrete progeny viruses in urine
[1, 9, 20, 22, 39]. JCV may also persist in other sites, including peripheral blood
lymphocytes, lymphoid tissues, and the central nervous system .