TY - JOUR
T1 - Refining the r-index
AU - Bannai, Hideo
AU - Gagie, Travis
AU - I, Tomohiro
N1 - Funding Information:
Partially funded by JSPS KAKENHI Grant Number JP16H02783.Partially funded by FONDECYT grant 1171058.Partially funded by JSPS KAKENHI Grant Number JP16K16009.
PY - 2020/4/6
Y1 - 2020/4/6
N2 - Gagie, Navarro and Prezza's r-index (SODA, 2018) promises to speed up DNA alignment and variation calling by allowing us to index entire genomic databases, provided certain obstacles can be overcome. In this paper we first strengthen and simplify Policriti and Prezza's Toehold Lemma (DCC '16; Algorithmica, 2017), which inspired the r-index and plays an important role in its implementation. We then show how to update the r-index efficiently after adding a new genome to the database, which is likely to be vital in practice. As a by-product of this result, we obtain an online version of Policriti and Prezza's algorithm for constructing the LZ77 parse from a run-length compressed Burrows-Wheeler Transform. Our experiments demonstrate the practicality of all three of these results. Finally, we show how to augment the r-index such that, given a new genome and fast random access to the database, we can quickly compute the matching statistics and maximal exact matches of the new genome with respect to the database.
AB - Gagie, Navarro and Prezza's r-index (SODA, 2018) promises to speed up DNA alignment and variation calling by allowing us to index entire genomic databases, provided certain obstacles can be overcome. In this paper we first strengthen and simplify Policriti and Prezza's Toehold Lemma (DCC '16; Algorithmica, 2017), which inspired the r-index and plays an important role in its implementation. We then show how to update the r-index efficiently after adding a new genome to the database, which is likely to be vital in practice. As a by-product of this result, we obtain an online version of Policriti and Prezza's algorithm for constructing the LZ77 parse from a run-length compressed Burrows-Wheeler Transform. Our experiments demonstrate the practicality of all three of these results. Finally, we show how to augment the r-index such that, given a new genome and fast random access to the database, we can quickly compute the matching statistics and maximal exact matches of the new genome with respect to the database.
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U2 - 10.1016/j.tcs.2019.08.005
DO - 10.1016/j.tcs.2019.08.005
M3 - Article
AN - SCOPUS:85070385571
SN - 0304-3975
VL - 812
SP - 96
EP - 108
JO - Theoretical Computer Science
JF - Theoretical Computer Science
ER -