Figure 2. The intronic mutation alters the splicing of KIF5A.

(A) RNA derived from blood (upper panel) from a healthy individual, an ALS patient not carrying the mutation, and individual III-11 carrying the KIF5A intronic mutation. RT-PCR was performed using RNA and previously described primers to amplify a wild-type (155 bp) splice form extending from exon 26 to exon 28.³ An extra band was observed at 127 base pairs indicating aberrant splicing in individual III-11 that was not present in the healthy and disease control subjects. RNA obtained from an IPS cell line (lower panel) derived from fibroblasts of individual III-11 and a control IPS cell line (A18945) showed the same pattern. (B) Sanger sequence analysis of the 127bp transcript/band observed in the patient confirmed the skipping of exon 27 of KIF5A yielding an out of frame and extended disrupted C-terminal peptide sequence.³ ALS = amyotrophic lateral sclerosis.