A genome rearrangement involving RNA segment 11 of a bovine rotavirus has been analysed by molecular cloning and sequencing. This revealed that the rearranged genome segment was generated by a head to tail concatemerisation of two almost full length copies of segment 11. The upstream copy of the gene has lost its 3' end and the downstream copy its 5' end. The truncation of the upstream copy of the gene occurs within the termination codon for VP11 converting it from a UAG to a UGA, the rearranged gene is therefore still able to encode a normal VP11. The possible mechanisms by which this rearrangement may have been generated are discussed.