Journal of Combinatorial Optimization

, Volume 11, Issue 4, pp 387–405 | Cite as

Inapproximability results for the lateral gene transfer problem

  • Bhaskar Dasgupta
  • Sergio Ferrarini
  • Uthra Gopalakrishnan
  • Nisha Raj Paryani


This paper concerns the Lateral Gene Transfer Problem. This minimization problem, defined by Hallett and Lagergren (2001), is that of finding the most parsimonious lateral gene transfer scenario for a given pair of gene and species trees. Our main results are the following:
  1. (a)

    We show that it is not possible to approximate the problem in polynomial time within an approximation ratio of 1 + ε, for some constant ε > 0 unless P = NP. We also provide explicit values of ε for the above claim.

  2. (b)

    We provide an upper bound on the cost of any 1-active scenario and prove the tightness of this bound.



Lateral gene transfer Phylogeny Inapproximability 


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Copyright information

© Springer Science + Business Media, LLC 2006

Authors and Affiliations

  • Bhaskar Dasgupta
    • 1
  • Sergio Ferrarini
    • 2
  • Uthra Gopalakrishnan
    • 1
  • Nisha Raj Paryani
    • 1
  1. 1.Department of Computer ScienceUniversity of Illinois at ChicagoChicago
  2. 2.Dipartimento di Elettronica e InformazionePolitecnico di MilanoMilanoItaly

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