Transcriptional sequencing (TS) is a method that differs considerably from conventional sequencing methods. These differences include the use RNA polymerases with rNTPs and 3'-dNTPs as substrates and terminators respectively, and initiation from double stranded promoters on templates of ds-DNA. We used TS in an attempt to sequence 33 clones whose electropherogram peaks suddenly became absent or weak with conventional sequencing methods. All of the TS reactions overcame the difficulty in sequencing the problematic target regions of the 33 clones. Therefore, TS can be applied to sequence not only GC-rich regions, but also whole genome sequences with a high GC content.