Abstract:An about 1.0 kb cDNA fragment was cloned from young leaves of Solanum tuberosum L. by RT-PCR method. Sequencing analysis showed that the cDNA had high identity with HMGR genes of S. tuberosum published, and exhibited 77.0%, 93.２%, and 77.1% identification with HMGR Ⅰ, HMGR Ⅱ, and HMGR Ⅲ respectively. 3′ UTR alignment showed that HMGR-c2 had 50.2%, 80.3%, and 50.7% identification with HMGR Ⅰ, HMGR Ⅱ, and HMGR Ⅲ respectively. The authors deduced that the cDNA may be a new member of HMGR Ⅱ gene subfamily. Results of Southern blotting suggested that there exists more than two copies in genomic DNA of potato. Northern blotting showed that the full-length mRNA of HMGR-c2 is about 2.0 kb. Analysis of quantitative RT-PCR showed that HMGR-c2 expressed in roots, stems and leaves, but the relative transcription levels in leaves is about two times than that in roots and stems.