Partial reverse-sequencing map of SMN1 clones for the patient with the p.Arg288Met mutation. (A) Antisense sequencing map of SMN1 clones. The C base (G in the sense sequence) is indicated by the black arrow, which is specific for SMN1 on exon 8. The red arrow indicates the position of the entire exon 7 sequence that was deleted in the SMN1 clone. (B) Antisense sequencing map of a normal individual. The G base (C in the sense sequence) is indicated by the black arrow and is specific for SMN1 on exon 7. The intact sequence of exon 7 can be seen between exons 6 and 8.