Estimation of the number of nucleotide substitutions when there are strong transition-transversion and G+C-content biases.
نویسنده
چکیده
A simple mathematical method is developed to estimate the number of nucleotide substitutions per site between two DNA sequences, by extending Kimura's (1980) two-parameter method to the case where a G+C-content bias exists. This method will be useful when there are strong transition-transversion and G+C-content biases, as in the case of Drosophila mitochondrial DNA.
منابع مشابه
Estimation of the Number of Nucleotide Substitutions
In the study of molecular evolution, it is important to know the number of nucleotide substitutions per site (d) between DNA sequences. There are many different methods for estimating this number (for reviews, see Nei 1987, chap. 5; Gojobori et al. 1990)) but all of them depend on some simplifying assumptions and do not always give reliable estimates. Two important factors that should be consid...
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Rates and patterns of synonymous and nonsynonymous substitutions have important implications for the origin and maintenance of mammalian isochores and the effectiveness of selection at synonymous sites. Previous studies of mammalian nuclear genes largely employed approximate methods to estimate rates of nonsynonymous and synonymous substitutions. Because these methods did not account for major ...
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Approximate methods for estimating the numbers of synonymous and nonsynonymous substitutions between two DNA sequences involve three steps: counting of synonymous and nonsynonymous sites in the two sequences, counting of synonymous and nonsynonymous differences between the two sequences, and correcting for multiple substitutions at the same site. We examine complexities involved in those steps ...
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ورودعنوان ژورنال:
- Molecular biology and evolution
دوره 9 4 شماره
صفحات -
تاریخ انتشار 1992