Crohn’s Disease and Early Exposure to Thiopurines are Independent Risk Factors for Mosaic Chromosomal Alterations in Patients with Inflammatory Bowel Diseases
Authors: Kakuta Yoichi , Iwaki Hideya , Umeno Junji , Kawai Yosuke , Kawahara Masahiro , Takagawa Tetsuya , Shimoyama Yusuke , Naito Takeo , Moroi Rintaro , Kuroha Masatake , Shiga Hisashi , Watanabe Kenji , Nakamura Shiro , Nakase Hiroshi , Sasaki Makoto , Hanai Hiroyuki , Fuyuno Yuta , Hirano Atsushi , Matsumoto Takayuki , Kudo Hisaaki , Minegishi Naoko , Nakamura Minoru , Hisamatsu Tadakazu , Andoh Akira , Nagasaki Masao , Tokunaga Katsushi , Kinouchi Yoshitaka , Masamune Atsushi ,   MENDEL Study Group, Sakuraba Hirotake , Ishiguro Yoh , Hokari Ryota , Araki Hiroshi , Motoya Satoshi , Kobayashi Taku , Nishida Atsushi , Ikeya Kentaro , Nakagawa Shoko , Miura Miki , Toyonaga Takahiko , Onodera Kei , Ishihara Shunji , Oshima Naoki , Katsurada Takehiko , Sasaki Yu , Otsuka Takafumi , Fujiya Mikihiro , Mizuno Shinta , Naganuma Makoto , Fujii Toshimitsu , Nagahori Masakazu , Arai Katsuhiro , Noguchi Mitsunori , Matsuura Minoru , Ohta Yuki , Nakagawa Tomoo , Takahara Masahiro , Hiraoka Sakiko , Shinozaki Masaru , Suzuki Yasuo , Matsuoka Katsuyoshi , Esaki Motohiro , Harada Akira , Ikegami Koji , Ohyama Hideaki , Korekawa Kai , Takahashi Sayumi , Makuuchi Motoki , Inomata Yushi , Shimoda Fumiko , Takahashi Takahiro , Yano Kota , Abe Izuru , Handa Tomoyuki , Masu Yutaro , Suzuki Kaoru , Hishinuma Kasumi , Kanazawa Yoshitake , Kimura Tomoya , Endo Katsuya , Negoro Kenichi , Kato Mai 
Published: November 2021

Abstract

Background and Aims
Mosaic chromosomal alterations [mCAs] increase the risk for haematopoietic malignancies and may be risk factors for several other diseases. Inflammatory bowel diseases [IBDs], including Crohn’s disease [CD] and ulcerative colitis [UC], are associated with mCAs, and patients may be at risk for haematopoietic malignancy development and/or modification of IBD phenotypes. In the present study, we screened patients with IBD for the presence of mCAs and explored the possible pathophysiological and genetic risk factors for mCAs.

Methods
We analysed mCAs in peripheral blood from 3339 patients with IBD and investigated the clinical and genetic risk factors for mCAs.

Results
CD and exposure to thiopurines before the age of 20 years were identified as novel independent risk factors for mCAs [odds ratio = 2.15 and 5.68, p = 1.17e-2 and 1.60e-3, respectively]. In contrast, there were no significant associations of disease duration, anti-tumour necrosis factor alpha antibodies, or other clinical factors with mCAs. Gene ontology enrichment analysis revealed that genes specifically located in the mCAs in patients with CD were significantly associated with factors related to mucosal immune responses. A genome-wide association study revealed that ERBIN, CD96, and AC068672.2 were significantly associated with mCAs in patients with CD [p = 1.56e-8, 1.65e-8, and 4.92e-8, respectively].

Conclusions
The difference in mCAs between patients with CD and UC supports the higher incidence of haematopoietic malignancies in CD. Caution should be exercised when using thiopurines in young patients with IBD, particularly CD, in light of possible chromosomal alterations.