Alal Eran, Kaitlin R. Graham, Kayla Vatalaro, Jillian McCarthy, Christin Collins, Heather Peters, Stephanie J. Brewster, Ellen Hanson, Rachel Hundley, Leonard Rappaport, Ingrid A. Holm, Isaac S. Kohane, Louis M. Kunkel
(A) RT-PCR of CADPS2 mRNA in blood from subsets of
patients with ASD (A1–A14) and control patients (C1–C10)
following the Sadakata et al. protocols (1). The 661-bp band represents the
full-length exon 1–5 fragment of CADPS2 mRNA, while
the 328-bp band is a result of exon 3 skipping. Four control samples (C1, C2, C6,
and C8) and 4 ASD samples (A3, A7, A8, and A9) were heterozygous for the exon
3–skipped isoform. The flanking marker is a 50-bp ladder. The
remaining samples showed only the 661-bp band (data not shown). (B)
Alignment of sequences obtained from the 328-bp bands of samples C1, C2, C6, and
A9 to human chromosome 7 showed that all sequences lacked exon 3. Sequencing the
661-bp band of A10 (which was representative of other samples not showing the
328-bp band) demonstrated that this fragment does include exon 3, as expected.
(C) RT-PCR of blood CADPS2 mRNA using a nested
amplification. A single major band (563 bp), indicating the presence of exons
2–5, is shown in all autistic samples. Control sample C14 was
apparently homozygous for a 230-bp band that resulted from skipping of exon 3.
(D) RT-PCR of cerebellar CADPS2 mRNA from
individuals with ASD and control individuals showed that all cerebella contained
the exon 3–skipped splice variant as a minor isoform (230-bp
fragment). M, low-DNA-mass ladder (Invitrogen).