  Most of major algorithms for phylogenetic tree reconstruction assume that
sequences in the analyzed set either do not have any offspring, or that parent
sequences can maximally mutate into just two descendants. The graph resulting
from such assumptions forms therefore a binary tree, with all the nodes labeled
as leaves. However, these constraints are unduly restrictive as there are
numerous data sets with multiple offspring of the same ancestors. Here we
propose a solution to analyze and visualize such sets in a more intuitive
manner. The method reconstructs phylogenetic tree by assigning the sequences
with offspring as internal nodes, and the sequences without offspring as leaf
nodes. In the resulting tree there is no constraint for the number of adjacent
nodes, which means that the solution tree needs not to be a binary graph only.
The subsequent derivation of evolutionary pathways, and pair-wise mutations,
are then an algorithmically straightforward, with edge's length corresponding
directly to the number of mutations. Other tree reconstruction algorithms can
be extended in the proposed manner, to also give unbiased topologies.
