Characterisation of a novel recombination event in the norovirus polymerase gene

This communication describes a novel recombination event in the norovirus genome. Similarity plot analysis of a nucleoticle fragment (1003 bp) amplified from a norovirus positive clinical specimen (IrIN05771) identified a previously undescribed recombination point in the 3' region of the polymerase gene (nucleotide position 4889 bp). Nucleotide multiple alignments demonstrated that Ir105N771 shared 78.6% and 94% identity with all other Irish norovirus sequences before and after the recombination point, respectively and confirmed the sequence as a genogroup II/type 4 recombinant. Ir105N771 shared more identity with Asian norovirus sequences. This is the first description of recombination within the norovirus polymerase and highlights the continuous genetic evolution of noroviruses. (C) 2007 Elsevier Inc. All rights reserved.