The JC virus (JCV) is a common human virus persisting in renal tissue. In immunocompromised individuals it may reactivate and cause progressive multifocal leukoencephalopathy (PML). JCV has also been implicated in cancerogenesis, leading to various brain tumors and cancers of gastrointestinal tract. In this study the JCV excretion in urine of 113 healthy Polish donors was analyzed. A 215-bp region of the viral gene coding for a major capsid protein VP1 was PCR-amplified and detected in 52 individuals (46.0%). The occurrence rate increased with age and was highest in the group of over 60-year-old donors (63.6%). Sequence analysis of the VP1 gene fragment revealed the following distribution of JCV genotypes in the investigated group: 1A, 31 (59.6%); 1B, 13 (25.0%); 2A, 2 (3.8%); and 2C, 6 samples (11.5%). The frequency and distribution of the JCV genotypes in the Polish population resembles that in other European countries, with the most abundant genotype 1 (84.6%). However, while in those countries the second most frequent genotype was usually 4, in the investigated group genotype 4 was not detected. J. Med. Virol. 80:1079-
1083, 2008. © 2008 Wiley-Liss, Inc.