Molecular mass analysis of PCR products derived from amplification of genomic DNA and of mRNA species derived by reverse transcriptase PCR.

(A) PCR amplification of exons 1 to 4 of genomic DNA from patient 1, his mother, and a normal control was performed as described in “Patients, materials, and methods.” The normal product is approximately 4.0-kb, and the product derived from amplification of exons 1 and 4 with exons 2 and 3 deleted is approximately 3.0-kb. (B) RT-PCR of mRNA prepared from whole blood was performed as described in “Patients, materials, and methods.” Left lane, markers; right lanes, 5, 10 and 13 μL of PCR product. The upper band is derived from a mRNA with exons 2 and 3 skipped, the lower band is derived from a mRNA species with exons 2, 3, and 4 skipped.