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CHAOS application details page
Create a chaos game representation plot for a sequence
A box is drawn and an AGCT is drawn at each corner. Starting from the middle, move half way to the corner of the box representing the first base in the sequence and draw a dot. Then for each subsequent base move half way to the corresponding box corner and draw a dot. Finally display the number and percentage values of AGCT bases. The result is an image of a square sprinkled with dots. Areas which aredevoid of dots (or heavily covered with dots) indicate short sequencemotifs that are unusually infrequent (or frequent). The sequence ofsuch motifs can be deduced by looking to see which quarter of teh squarethe region is in - the letter that this quarter belongs to is the firstbase of the motif. The quarter is then quartered again and theappropriate base letters are assigned to the corners of the quarter -the eigth part that the region is in gives the second base of the motif. The process continues until you have identified the 1/16th or 1/32nd,etc. of the original square containing the unusual region and you nowhave the sequence of the motif.
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