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arXiv · 2103.06665

Arc-Completion of 2-Colored Best Match Graphs to Binary-Explainable Best Match Graphs

David Schaller·Manuela Geiß·Marc Hellmuth·Peter F. Stadler
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Abstract

Best match graphs (BMGs) are vertex-colored digraphs that naturally arise in mathematical phylogenetics to formalize the notion of evolutionary closest genes w.r.t. an a priori unknown phylogenetic tree. BMGs are explained by unique least resolved trees. We prove that the property of a rooted, leaf-colored tree to be least resolved for some BMG is preserved by the contraction of inner edges. For the special case of two-colored BMGs, this leads to a characterization of the least resolved trees (LRTs) of binary-explainable trees and a simple, polynomial-time algorithm for the minimum cardinality completion of the arc set of a BMG to reach a BMG that can be explained by a binary tree.

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David Schaller, Manuela Geiß, Marc Hellmuth, Peter F. Stadler. 2021-03-11. Arc-Completion of 2-Colored Best Match Graphs to Binary-Explainable Best Match Graphs. https://arxiv.org/abs/2103.06665

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