Genomic organization of potato CCS gene(s) revealed by Southern-blot analysis. Genomic DNA from potato cv Bintje was digested with the following restriction enzymes: XhoI (Xo), XbaI (Xa), HindIII (H), EcoRV (EV), BamHI (B), and EcoRI (EI). The immobilized fragments were hybridized with the TDFL431 fragment.