Figure 1.

Clinical and genomic features of a case with a novel APC mosaicism. (a) Colonic adenomatous polyposis and fundic grand polyps of the colon. (b) Pedigree chart. DNA from the peripheral lymphocytes of the parent-proband trio (proband, AGFAP001-1; his father, AGFAP001-2; and his mother, AGFAP001-3) was used for the APC mutation analysis using deep sequencing. (c) Confirmation of the c.834+2T>C mutation by Sanger sequencing using DNA from normal colonic mucosa (subject 1 and 2; arrowheads) and colonic adenomatous polyp (subject 1 and 2; arrows). (d) Transcriptional analysis. Because we detected a mosaic mutation at the spliced donor site (Table 1), the mutation was potentially capable of resulting in an extended amino acid translation at intron 7. We detected an RT–PCR product using electrophoresis that was transcribed into an aberrant mRNA with intron 7. (e) Direct sequencing followed by TA cloning revealed that the c.834+2T>C mutation induced aberrant transcription and produced a truncated APC protein. ^☆the stop codon (TAA). mRNA, messenger RNA.