Genomic insights into familial adenomatous polyposis: unraveling a rare case with whole APC gene deletion and intellectual disability

Hiroki Tanabe; Masami Ijiri; Kenji Takahashi; Honoka Sasagawa; Tomomi Kamanaka; Shohei Kuroda; Hiroki Sato; Takeo Sarashina; Yusuke Mizukami; Yoshio Makita; Toshikatsu Okumura

doi:10.1038/s41439-024-00270-3

Genomic insights into familial adenomatous polyposis: unraveling a rare case with whole APC gene deletion and intellectual disability

Hum Genome Var. 2024 Mar 29;11(1):13. doi: 10.1038/s41439-024-00270-3.

Authors

Hiroki Tanabe^{1

2

3}, Masami Ijiri⁴, Kenji Takahashi^{5

6}, Honoka Sasagawa⁷, Tomomi Kamanaka⁸, Shohei Kuroda⁴, Hiroki Sato⁶, Takeo Sarashina⁸, Yusuke Mizukami^{5

6}, Yoshio Makita⁷, Toshikatsu Okumura⁶

Affiliations

¹ Oncology Center, Asahikawa Medical University Hospital, Asahikawa, Japan. tant@asahikawa-med.ac.jp.
² Genetic Oncology Department, Asahikawa Medical University Hospital, Asahikawa, Japan. tant@asahikawa-med.ac.jp.
³ Department of Genetic Counseling, Asahikawa Medical University Hospital, Asahikawa, Japan. tant@asahikawa-med.ac.jp.
⁴ Department of Gastroenterology, Japanese Red Cross Asahikawa Hospital, Asahikawa, Japan.
⁵ Genetic Oncology Department, Asahikawa Medical University Hospital, Asahikawa, Japan.
⁶ Department of Internal Medicine, Asahikawa Medical University, Asahikawa, Japan.
⁷ Department of Genetic Counseling, Asahikawa Medical University Hospital, Asahikawa, Japan.
⁸ Oncology Center, Asahikawa Medical University Hospital, Asahikawa, Japan.

Abstract

A young patient diagnosed with advanced colon cancer and liver metastasis was found to have familial adenomatous polyposis (FAP) through comprehensive genomic analysis. Whole-genome array comparative genomic hybridization (aCGH) revealed germline deletions at chromosome 5q22.1-22.2 encompassing the entire APC gene. The patient and her son exhibited mild intellectual disability without developmental delay. This case highlights the need for further exploration of the characteristics associated with whole APC deletions. aCGH is a valuable tool for studying FAP and provides a detailed analysis of large deletions.