Identification of a novel RhD-CE-D gene associated with D^VI type I variant. (A) Southern blot (left) and exon PCR assay (right). DNAs were digested with Sph I and hybridized with an Rh cDNA probe spanning exons 4 to 7. Lane 1, Rh-positive (DCCee); 2, Rh-negative (dccee); 3, D^VIccEe (T.S.); and 4, D^VIccEe (V.S.). The size (in kilobases), gene origin, and exon content of the various bands are indicated. The 10.8-kb new fragment is seen in T.S. and V.S. only. Exon PCR assay was performed exactly as described.3 Shown is a typical polyacrylamide gel electrophoresis analysis for exons 4, 5, and 6 PCR products digested with the restriction enzymes, Bcl I, Taq I, and Rsa I. M, φX174 DNA size markers; −, uncut; +, digested. The expected size (in base pairs) of various bands is indicated at the right margin. (B) Diagram for the origin of the D^VI type I gene. The two crosses denote the sites for recombination by which a D-CE-D hybrid is formed along with the relocation of the Sph I fragments. In the hybrid gene, exons 4 and 5 from the RhCE gene are flanked by exons from the RhD gene.