Sentence examples for substitution direction from inspiring English sources

In this analysis, the frequency of substitution direction in rat may be effected by some nucleotide substitutions occurred in the common ancestor of mouse and T. muenninki.

By contrast, this strong bias in substitution direction was not detected in the middle region of T. muenninki neo-sex chromosomes or in any region of rat and mouse autosomes (Table  1).

At a given position, if T. muenninki had a G-allele and the other species shared an A-allele, the substitution direction was inferred to be from A to G in T. muenninki.

Custom written C scripts were used to estimate the G + C content and the frequency of each substitution direction in the aligned noncoding and coding sequences among T. muenninki, M. musculus, and R. norvegicus, with or without guinea pig (Cavia porcellus) as outgroup.

The estimation of nucleotide substitution directions in the three species by the maximum parsimony principle.

As an additional analysis of substitution spectrum in the genetically diverged regions between neo-sex chromosomes, we estimated the frequencies of substitution directions in each neo-sex derived neo-sex derivednoncodingsequenceh betoeen the neo-X andistinguishcomparing with mouse sequence.

Frameshifts were found in four genes on the neo-sex chromosomes (Additional file 1: Table S2), and the coding sequences of these genes were excluded from the following substitution-direction analysis.

Therefore, we also performed the substitution-direction analysis among T. muenninki, mouse, and rat with guinea pig as outgroup to compare T. muenninki with rat more properly (Additional file 1: Table S3).

Substitution-direction analysis disclosed that sequence evolution toward GC-richness, which positively correlates with recombination activity, occurred in the peritelomeric regions, but not middle regions of the neo-sex chromosomes.

Therefore, we detected variations in G + C content, which is positively correlated with recombination activity [ 12, 13, 23], by substitution-direction analysis using 116 gene sequences from the peritelomeric, middle, and pericentromeric regions of T. muenninki neo-sex chromosomes, to reveal recombination activity in different chromosomal locations.

Out of the 780,000 (approximately) amino acid substitutions between the aligned proteome sequences, there are 272,000 substitutions in the direction predicted by the nucleotide bias and 221,000 in the opposite direction a difference of more than 50,000 amino acid substitutions (see table 1).