Restrictive motif discovering method

The invention discloses a restrictive motif discovering method and relates to the field of biological information. The method comprises the steps of 1, establishing a dictionary table used for storing pattern instances of a specified pattern P; 2, listing all instance sets I={I1...IN} of the specified pattern P in the dictionary table according to the lexicographic order, wherein Ii is a motif instance; 3, conducting comparative validation on each motif instance Ii and a nucleotide sequence to be detected, and outputting the ith instance which only appears in the nucleotide positive example sequence set to be detected and does not appear in the counter example sequence set as the motif which meets the conditions finally. Restrictive motif discovery is achieved with the simple method. The final experiment proves that all the motifs meeting the conditions can always be discovered with the reverse index algorithm within a reasonable period of time, and then the effectiveness of the algorithm is guaranteed.