We have begun the molecular characterization of genes encoding napin, the 1.7 S embryo-specific storage protein of Brassica napus. Genomic Southern blot analysis indicates that napin is encoded by a multigene family comprised of a minimum of 16 genes. Two DNA fragments containing single napin genes have been recovered from B. napus genomic libraries. We have determined the nucleotide sequence of one member of the napin gene family, gNa. The gene has a simple structure lacking introns and containing the canonical features expected for genes transcribed by RNA polymerase II. The site of the initiation of transcription was determined to be 37 base pairs upstream of the initiation codon by S1 and primer extension analyses. A gene-specific hybridization probe from the 3' non-translated portion of gNa was used to demonstrate transcription of gNa.