Size analysis of PCR products from cDNA. Primers were chosen on exon 4 and exon 10 (Table 1). The PCR products were separated in agarose and visualized with ethidium bromide. Lane 1 contains material from a healthy control donor, lane 2 from the youngest patient, lane 3 from the eldest patient, lane 4 from the mother of the patients, and lane 5 from the maternal grandmother of the patients. Lane M contains size markers of 100 bp.