ABSTRACT
Organization cDNA clones have a defined organization, especially those synthesized using oligo(dT) as primer. Usually a run of A residues is present at one end of the clone which defines its 3-end, and at some variable distance upstream of this there will be an open reading frame (ORF) ending in a stop codon (see Topic P1). If the cDNA clone is complete, it will have an ATG start codon, preceded usually by only 20-100 nt. As genomic clones from eukaryotes are larger, and may contain intron sequences, as well as nontranscribed sequences, they provide
