Figure 3

Biases in the location of sequence motifs found in the chicken promoter. (A) The locations of STRs and PQSs are shown in conjunction with a CpG island (CGI). Upstream and downstream CGI indicate the locations of sequence motifs. “Overlapped” means that at least part of a sequence motif is overlapped with a CGI. “Intervened” is used when a sequence motif is found to be flanked by two or more CGIs (not overlapped). There is significant difference in the locations between di- and trinucleotide repeats (Fisher’s exact test; p <0.001). (B) The distribution of trinucleotide repeats in chicken promoter. Trinucleotide repeats are classified into four categories by the number of guanine or cytosine in each repeat unit. Note that no trinucleotide repeat was found in the position at -901 to -1000 bp (asterisk).