Figure 4 (A) Reverse transcription (RT) PCR analysis using primers in exon 2 and 5 of the AP1S2 cDNA. Agarose‐gel electrophoresis of RT‐PCR products generated with lymphoblasts from patient (V1) and from a control subject (wild type; wt). (B) Sequence analysis of RT‐PCR products from the patient V1 and consequences of the splice mutation at the protein level.