Similarity studies of DNA sequences based on a new 2D graphical representation.

We denoted the four nucleotides, A, T, G and C, as four two-component vectors, and illustrated a nucleotide sequence as a curve in the 2D space by concatenating the vectors representing the nucleotides in the sequence. We studied the similarities among multiple nucleotide sequences by comparing their corresponding curves, with the beta-globin genes from 7 species as an example.