Concept explainers
To review:
The expected per-site mutation rate on the basis of the previous answer, assuming that the synonymous substitutions are neutral.
Given:
A hypothetical gene is taken. The sequencing of one of the exons of this gene has been done in four species. A matrix is provided below that represents the number of nonsynonymous (below the diagonal) and synonymous (above the diagonal) substitutions between different pairs of species (Figure 1). There are 600 synonymous and 2,000 nonsynonymous sites in the exon of this gene.
Figure 1: A matrix of synonymous and nonsynonymous substitutions between different pairs of species.
Introduction:
Biologists are able make inferences about the natural selections, operating in the environment, by the study of molecular evolution patterns of genes. These inferences are important to know about the gene functions and their evolution over the time, in response to the new function and conditions. According to the given Figure 1, one exon of this gene is sequenced in four species. The data of synonymous and nonsynonymous substitutions and the phylogeny of the species of the Drosophila specie are given. There are 2,000 nonsynonymous and 600 synonymous substitutions sites of the exon.
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EBK LIFE: THE SCIENCE OF BIOLOGY
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