Use of sanger and next-generation sequencing to screen for mosaic and intronic APC variants in unexplained colorectal polyposis patients

In this study, we investigated 80 unexplained colorectal polyposis patients without germline pathogenic variants in known polyposis predisposing genes to detect mosaic and deep intronicAPC variants. All patients developed more than 50 colorectal polyps, with adenomas being predominantly observed. To detectAPC mosaicism, we performed next-generation sequencing (NGS) in leukocyte DNA. Furthermore, using Sanger sequencing, the cohort was screened for the following previously reported deep intronic pathogenic germlineAPC variants: c.1408  + 731C >  T, p.(Gly471Serfs*55), c.1408 + 735A >  T, p.(Gly471Serfs*55), c.1408 + 729A >  G, p.(Gly471Serfs*55) and c.532-941G >  A, p.(Phe178Argfs*22). We did not detect mosaic or intronicAPC variants in the screened unexplained colorectal polyposis patients. The results of this study indicate that the deep intronicAPC variants investigated in this study are not a cause of colorectal polyposis in this Dutch population. In addition, NGS did not detect any further mosaic variants in our cohort.
Source: Familial Cancer - Category: Cancer & Oncology Source Type: research