The genome is bipartite, unique among ssDNA viruses, with two linear segments of ~6 and 6.5 kilobases (kb).
These segments and the complementary strands are that are packaged separately giving rise to 4 different types of full particles.
The open reading frame 4 (VD1-ORF4) is 3318 nucleotides (bases) in length and encodes a predicted (3318/3 − 1 =) 1105 amino acid protein which has a conserved DNA polymerase motif.
[3] Comprehensive analysis of bidnavirus genes has shown that these viruses have evolved from a parvovirus ancestor from which they inherit a jelly-roll capsid protein and a superfamily 3 helicase.
[4] It has been further suggested that the key event that led to the separation of the bidnaviruses from parvoviruses was the acquisition of the PolB gene.