Cargando…

γ-MYN: a new algorithm for estimating Ka and Ks with consideration of variable substitution rates

BACKGROUND: Over the past two decades, there have been several approximate methods that adopt different mutation models and used for estimating nonsynonymous and synonymous substitution rates (Ka and Ks) based on protein-coding sequences across species or even different evolutionary lineages. Among...

Descripción completa

Detalles Bibliográficos
Autores principales: Wang, Da-Peng, Wan, Hao-Lei, Zhang, Song, Yu, Jun
Formato: Texto
Lenguaje:English
Publicado: BioMed Central 2009
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2702329/
https://www.ncbi.nlm.nih.gov/pubmed/19531225
http://dx.doi.org/10.1186/1745-6150-4-20
_version_ 1782168759756128256
author Wang, Da-Peng
Wan, Hao-Lei
Zhang, Song
Yu, Jun
author_facet Wang, Da-Peng
Wan, Hao-Lei
Zhang, Song
Yu, Jun
author_sort Wang, Da-Peng
collection PubMed
description BACKGROUND: Over the past two decades, there have been several approximate methods that adopt different mutation models and used for estimating nonsynonymous and synonymous substitution rates (Ka and Ks) based on protein-coding sequences across species or even different evolutionary lineages. Among them, MYN method (a Modified version of Yang-Nielsen method) considers three major dynamic features of evolving DNA sequences–bias in transition/transversion rate, nucleotide frequency, and unequal transitional substitution but leaves out another important feature: unequal substitution rates among different sites or nucleotide positions. RESULTS: We incorporated a new feature for analyzing evolving DNA sequences–unequal substitution rates among different sites–into MYN method, and proposed a modified version, namely γ (gamma)-MYN, based on an assumption that the evolutionary rate at each site follows a mode of γ-distribution. We applied γ-MYN to analyze the key estimator of selective pressure ω (Ka/Ks) and other relevant parameters in comparison to two other related methods, YN and MYN, and found that neglecting the variation of substitution rates among different sites may lead to biased estimations of ω. Our new method appears to have minimal deviations when relevant parameters vary within normal ranges defined by empirical data. CONCLUSION: Our results indicate that unequal substitution rates among different sites have variable influences on ω under different evolutionary rates while both transition/transversion rate ratio and unequal nucleotide frequencies affect Ka and Ks thus selective pressure ω. REVIEWERS: This paper was reviewed by Kateryna Makova, David A. Liberles (nominated by David H Ardell), Zhaolei Zhang (nominated by Mark Gerstein), and Shamil Sunyaev.
format Text
id pubmed-2702329
institution National Center for Biotechnology Information
language English
publishDate 2009
publisher BioMed Central
record_format MEDLINE/PubMed
spelling pubmed-27023292009-06-27 γ-MYN: a new algorithm for estimating Ka and Ks with consideration of variable substitution rates Wang, Da-Peng Wan, Hao-Lei Zhang, Song Yu, Jun Biol Direct Research BACKGROUND: Over the past two decades, there have been several approximate methods that adopt different mutation models and used for estimating nonsynonymous and synonymous substitution rates (Ka and Ks) based on protein-coding sequences across species or even different evolutionary lineages. Among them, MYN method (a Modified version of Yang-Nielsen method) considers three major dynamic features of evolving DNA sequences–bias in transition/transversion rate, nucleotide frequency, and unequal transitional substitution but leaves out another important feature: unequal substitution rates among different sites or nucleotide positions. RESULTS: We incorporated a new feature for analyzing evolving DNA sequences–unequal substitution rates among different sites–into MYN method, and proposed a modified version, namely γ (gamma)-MYN, based on an assumption that the evolutionary rate at each site follows a mode of γ-distribution. We applied γ-MYN to analyze the key estimator of selective pressure ω (Ka/Ks) and other relevant parameters in comparison to two other related methods, YN and MYN, and found that neglecting the variation of substitution rates among different sites may lead to biased estimations of ω. Our new method appears to have minimal deviations when relevant parameters vary within normal ranges defined by empirical data. CONCLUSION: Our results indicate that unequal substitution rates among different sites have variable influences on ω under different evolutionary rates while both transition/transversion rate ratio and unequal nucleotide frequencies affect Ka and Ks thus selective pressure ω. REVIEWERS: This paper was reviewed by Kateryna Makova, David A. Liberles (nominated by David H Ardell), Zhaolei Zhang (nominated by Mark Gerstein), and Shamil Sunyaev. BioMed Central 2009-06-16 /pmc/articles/PMC2702329/ /pubmed/19531225 http://dx.doi.org/10.1186/1745-6150-4-20 Text en Copyright © 2009 Wang et al; licensee BioMed Central Ltd. http://creativecommons.org/licenses/by/2.0 This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( (http://creativecommons.org/licenses/by/2.0) ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Research
Wang, Da-Peng
Wan, Hao-Lei
Zhang, Song
Yu, Jun
γ-MYN: a new algorithm for estimating Ka and Ks with consideration of variable substitution rates
title γ-MYN: a new algorithm for estimating Ka and Ks with consideration of variable substitution rates
title_full γ-MYN: a new algorithm for estimating Ka and Ks with consideration of variable substitution rates
title_fullStr γ-MYN: a new algorithm for estimating Ka and Ks with consideration of variable substitution rates
title_full_unstemmed γ-MYN: a new algorithm for estimating Ka and Ks with consideration of variable substitution rates
title_short γ-MYN: a new algorithm for estimating Ka and Ks with consideration of variable substitution rates
title_sort γ-myn: a new algorithm for estimating ka and ks with consideration of variable substitution rates
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2702329/
https://www.ncbi.nlm.nih.gov/pubmed/19531225
http://dx.doi.org/10.1186/1745-6150-4-20
work_keys_str_mv AT wangdapeng gmynanewalgorithmforestimatingkaandkswithconsiderationofvariablesubstitutionrates
AT wanhaolei gmynanewalgorithmforestimatingkaandkswithconsiderationofvariablesubstitutionrates
AT zhangsong gmynanewalgorithmforestimatingkaandkswithconsiderationofvariablesubstitutionrates
AT yujun gmynanewalgorithmforestimatingkaandkswithconsiderationofvariablesubstitutionrates