Distribution of different di- and trinucleotide repeats in genomic and EST sequences of cucumber and selected seven other plant species. Frequency values were expressed as number of repeats per million base pairs of sequence. Species were arranged in order to their phylogenetic relationship with cucumber. All species considered, repeats of AT (T = 4.53, P = 0.0021), AC (T = 1.34, P = 0.018), and AAT (T = 2.68, P = 0.028) were significantly more frequent in genomic - than in EST data, whereas ACT (T = 4.25, P < 0.001) and ACC (T = 7.09, P < 0.001) were more abundant in EST sequence. Detailed information on frequencies of individual di- and trinucleotide repeat motifs was provided in Additional file 1 (supplement Tables S2a and S3a).