TY - JOUR

T1 - Optimal computation of all tandem repeats in a weighted sequence

AU - Barton, Carl

AU - Iliopoulos, Costas S.

AU - Pissis, Solon P.

PY - 2014/8/16

Y1 - 2014/8/16

N2 - Background: Tandem duplication, in the context of molecular biology, occurs as a result of mutational events in which an original segment of DNA is converted into a sequence of individual copies. More formally, a repetition or tandem repeat in a string of letters consists of exact concatenations of identical factors of the string. Biologists are interested in approximate tandem repeats and not necessarily only in exact tandem repeats. A weighted sequence is a string in which a set of letters may occur at each position with respective probabilities of occurrence. It naturally arises in many biological contexts and provides a method to realise the approximation among distinct adjacent occurrences of the same DNA segment. Results: Crochemore's repetitions algorithm, also referred to as Crochemore's partitioning algorithm, was introduced in 1981, and was the first optimal O(nlogn)-time algorithm to compute all repetitions in a string of length n. In this article, we present a novel variant of Crochemore's partitioning algorithm for weighted sequences, which requires optimal O(nlogn) time, thus improving on the best known On2-time algorithm (Zhang et al., 2013) for computing all repetitions in a weighted sequence of length n.

AB - Background: Tandem duplication, in the context of molecular biology, occurs as a result of mutational events in which an original segment of DNA is converted into a sequence of individual copies. More formally, a repetition or tandem repeat in a string of letters consists of exact concatenations of identical factors of the string. Biologists are interested in approximate tandem repeats and not necessarily only in exact tandem repeats. A weighted sequence is a string in which a set of letters may occur at each position with respective probabilities of occurrence. It naturally arises in many biological contexts and provides a method to realise the approximation among distinct adjacent occurrences of the same DNA segment. Results: Crochemore's repetitions algorithm, also referred to as Crochemore's partitioning algorithm, was introduced in 1981, and was the first optimal O(nlogn)-time algorithm to compute all repetitions in a string of length n. In this article, we present a novel variant of Crochemore's partitioning algorithm for weighted sequences, which requires optimal O(nlogn) time, thus improving on the best known On2-time algorithm (Zhang et al., 2013) for computing all repetitions in a weighted sequence of length n.

KW - IUPAC notation

KW - Tandem repeats

KW - Weighted sequences

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U2 - 10.1186/s13015-014-0021-5

DO - 10.1186/s13015-014-0021-5

M3 - Article

AN - SCOPUS:84906837284

VL - 9

JO - Algorithms for Molecular Biology

JF - Algorithms for Molecular Biology

SN - 1748-7188

IS - 1

M1 - 21

ER -