A 3356bp genomic DNA fragment was isolated from rapeseed genome by using nested PCR and genomic walking PCR strategies.It contained 1587bp of transcription region,with 1389bp of coding sequences without intron,encoding a polypeptide of 462 amino acid residues.KCS13 genes were found in both A and C genome species of Brassica.The KCS13 gene was shown to express predominantly in flower buds,stems,leaves and seeds,but not in roots.