Tissue-specific splicing of exons downstream from the deletion. (Top) Schematic representation of the PCR strategy; the expected PCR products and their sizes in basepairs are shown. (Bottom) RT-PCR on reticulocyte (R) or lymphoblastoid cell (L) mRNA, using primers XIII/XIV (A) or primers XV/XVI (B). C, control; I.2, proposita; M, size marker.