1. A method of extracting an extensible motif from a sequence, said method comprising: on a processing unit of a computer, assigning a significance, comprising an extensible z-score, to an extensible motif within said sequence based upon a syntactic and statistical analysis; and identifying an extensible motif having a significance that exceeds a predetermined threshold, wherein said assigning said significance comprises restricting a computation of the extensible z-score for each of said motifs to classes of maximal motifs.
12. The method of claim 1 , further comprising displaying a list of identified extensible motifs.