Legend: (A) Fluorescent fragment length analysis of a PCR fragment
containing the GGGGCC repeat in C9orf72 in 4 patients (II-1,
III-1, II-2 and II-4) and one unaffected spouse (II-0). A lack of transmission
from the affected parent (II-1) to the affected offspring (III-1) is seen.
Numbers under the peaks indicate number of GGGGCC hexanucleotide repeats. (B)
PCR products of repeat-primed PCR reactions separated on an ABI3730 DNA Analyzer
and visualized by GENEMAPPER software. Electropherograms are zoomed to 2,000
relative fluorescence units to show stutter amplification. One expanded repeat
carrier (II-1) and one healthy control are shown. (C) Southern blotting of 3
expanded repeat carriers and one unaffected spouse using genomic DNA extracted
from blood. Patients with expanded repeats (II-1, III-1 and II-2) show
additional alleles ranging from 5–23 kb, while the normal spouse (II-0)
only shows the expected ~2.3 kb wild-type allele.