EBV-transformed patient cells exhibit the same aberrant γc mRNA splicing pattern as previously studied patient PBMCs. RT-PCR analysis showed a single 439 bp product representing correctly spliced γc mRNA in healthy control-derived EBV-γc^wt cells (lane 4) and 3 products of 439, 499 and 650 bp in patient-derived EBV-γc^low cells (lane 6). These represent trace amounts of correctly spliced γc mRNA, a species with aberrant intron 3 splicing and a predominant species with complete failure of intron 3 splicing, respectively. M indicates Molecular Weight Marker VIII (Roche); NTC, no template control; EBV-γc^wt, healthy control; EBV-γc^low, patient; -, no RT controls.