Similarities and Dissimilarities among the DNA Sequences

Different graphical representations generally involve different artifacts in the analysis and will be accompanied by different signal-to-noise ratios. The way to reduce the chance of inclnding false similarity results is to use several 2-D graphical representations simultaneously. In this way, one may expect that accidental coincidences in the similarity-dissimilarity testing will be more likely to be detected, which will resnlt in more reliable numerical data. 

In Table 13.5, we have collected the data on similarity-dissimilarity between the nine species based on the comparison of the first exon of their p-globin gene. All the similarity-dissimilarity values have been calculated as the corresponding distance between vectors (Aj, A2, A3, A4) of Table 13.4, and have been normalized so that the smallest entry equals 1, which occurs for the pair human-gorilla. If Table 13.5 is viewed in isolation, it may pass on some incorrect information. In order to extract more reliable information from such 2-D representations of DNA, one may consider using simultaneous similarity tables based on different grids. 

It is of interest to see how this similarity-dissimilarity table parallels other similarity-dissimilarity tables. We have selected Table 13.6 derived nsing Clnstal Omega, which can be taken as a standard for snch a comparison. Table 13.6 was 

Similarity-Dissimilarity Table for the Nine Species with Spiral Representations of DNA Based on the Four Eigenvalues of Table 13.4 

Similarity between the Nine Species Based on Clustal Omega Program 

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