In this study, the molecular characterization of a rare G8P group A rotavirus (GARV) strain detected in Northern Italy during the 2004-2005 epidemiological rotavirus season is described. Two hundred and seventy three rotavirus-like particle positive stools out of 856 stools from children (31.9%) hospitalized with gastroenteritis were analyzed using polyacrilamide gel electrophoresis and 271 GARVs were genotyped by VP7 and VP4 specific RT-PCRs. One strain (PR/1300/04) with a long electropherotype (e-type) displayed the G8 specificity and was VP4 un-typeable. The P and the subgroup (SG) specificities were determined by sequencing the VP4 and the VP6 gene, respectively. The PR/1300/04 strain exhibited P and SGI specificities. By sequence and phylogenetic analyses of the VP4, VP6 and VP7 amplicons, the PR/1300/04 VP4 and VP6 genes were demonstrated to be of human rotavirus origin, with the VP4 gene closely related to the human Italian PA169 strain (G6P), while the VP7 gene was of animal origin (bovine). These data suggest that the Italian PR/1300/04 strain could be a reassortant between a PA169-like Italian strain with P specificity, long e-type and SGI, and a G8 animal strain. The increasing number of reports of atypical GARVs in humans suggests that interspecies transmission of genes greatly contributes to the GARV genetic evolution.