The newly developed method of detecting JCV genotypes using a DNA chip has numerous advantages, making the investigation of unidentified cadavers both quicker and easier; this method will be very effective in locations where there are many unidentified bodies following large-scale disasters, such as those resulting from the Indonesian tsunami and international terrorism. Dental charts, fingerprints, and DNA are generally used for individual identification. However, even when DNA typing of an unidentified cadaver has been performed, it remains impossible to identify the victim quickly if there are no candidates to be checked against. Each genotype of the JCV which parasitizes the kidneys of most humans and excretes progeny virus in urine, has relatively small distinct distribution domains throughout the world. The same viral strain is maintained throughout an individual’s life, regardless of geographic relocation of the hose, making it possible to estimate the geographic origins of unidentified cadavers by detecting JCV genotypes from human renal tissue samples and urinary stains at crime scenes. This method has become an integral part of police investigations in Japan, as it effectively aids human identification by narrowing down the geographical areas of origin. Despite the advantages, the viral genotypes must be obtained by a lengthy process of viral DNA extraction, PCR amplification, cloning, sequencing, and phylogenetic analysis. In order to expedite this lengthy process, a new method was developed using a DNA chip which uses PCR amplification to type the hypervariable region of the virus with fluorescent dye combined with dCTP. The amplified fragments are then hybridized to type-specific probes fixed on a DNA chip, and the fluorescent signals of fragments hybridized with type-specific probes are scanned by a detector. Tables, figures, references