1
|
Disciglio V, Forte G, Fasano C, Sanese P, Lepore Signorile M, De Marco K, Grossi V, Cariola F, Simone C. APC Splicing Mutations Leading to In-Frame Exon 12 or Exon 13 Skipping Are Rare Events in FAP Pathogenesis and Define the Clinical Outcome. Genes (Basel) 2021; 12:genes12030353. [PMID: 33670833 PMCID: PMC7997234 DOI: 10.3390/genes12030353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/22/2021] [Accepted: 02/22/2021] [Indexed: 11/16/2022] Open
Abstract
Familial adenomatous polyposis (FAP) is caused by germline mutations in the tumor suppressor gene APC. To date, nearly 2000 APC mutations have been described in FAP, most of which are predicted to result in truncated protein products. Mutations leading to aberrant APC splicing have rarely been reported. Here, we characterized a novel germline heterozygous splice donor site mutation in APC exon 12 (NM_000038.5: c.1621_1626+7del) leading to exon 12 skipping in an Italian family with the attenuated FAP (AFAP) phenotype. Moreover, we performed a literature meta-analysis of APC splicing mutations. We found that 119 unique APC splicing mutations, including the one described here, have been reported in FAP patients, 69 of which have been characterized at the mRNA level. Among these, only a small proportion (9/69) results in an in-frame protein, with four mutations causing skipping of exon 12 or 13 with loss of armadillo repeat 2 (ARM2) and 3 (ARM3), and five mutations leading to skipping of exon 5, 7, 8, or (partially) 9 with loss of regions not encompassing known functional domains. The APC splicing mutations causing skipping of exon 12 or 13 considered in this study cluster with the AFAP phenotype and reveal a potential molecular mechanism of pathogenesis in FAP disease.
Collapse
Affiliation(s)
- Vittoria Disciglio
- Medical Genetics, National Institute of Gastroenterology “S. de Bellis” Research Hospital, Castellana Grotte, 70013 Bari, Italy; (G.F.); (C.F.); (P.S.); (M.L.S.); (K.D.M.); (V.G.); (F.C.)
- Correspondence: (V.D.); (C.S.)
| | - Giovanna Forte
- Medical Genetics, National Institute of Gastroenterology “S. de Bellis” Research Hospital, Castellana Grotte, 70013 Bari, Italy; (G.F.); (C.F.); (P.S.); (M.L.S.); (K.D.M.); (V.G.); (F.C.)
| | - Candida Fasano
- Medical Genetics, National Institute of Gastroenterology “S. de Bellis” Research Hospital, Castellana Grotte, 70013 Bari, Italy; (G.F.); (C.F.); (P.S.); (M.L.S.); (K.D.M.); (V.G.); (F.C.)
| | - Paola Sanese
- Medical Genetics, National Institute of Gastroenterology “S. de Bellis” Research Hospital, Castellana Grotte, 70013 Bari, Italy; (G.F.); (C.F.); (P.S.); (M.L.S.); (K.D.M.); (V.G.); (F.C.)
| | - Martina Lepore Signorile
- Medical Genetics, National Institute of Gastroenterology “S. de Bellis” Research Hospital, Castellana Grotte, 70013 Bari, Italy; (G.F.); (C.F.); (P.S.); (M.L.S.); (K.D.M.); (V.G.); (F.C.)
| | - Katia De Marco
- Medical Genetics, National Institute of Gastroenterology “S. de Bellis” Research Hospital, Castellana Grotte, 70013 Bari, Italy; (G.F.); (C.F.); (P.S.); (M.L.S.); (K.D.M.); (V.G.); (F.C.)
| | - Valentina Grossi
- Medical Genetics, National Institute of Gastroenterology “S. de Bellis” Research Hospital, Castellana Grotte, 70013 Bari, Italy; (G.F.); (C.F.); (P.S.); (M.L.S.); (K.D.M.); (V.G.); (F.C.)
| | - Filomena Cariola
- Medical Genetics, National Institute of Gastroenterology “S. de Bellis” Research Hospital, Castellana Grotte, 70013 Bari, Italy; (G.F.); (C.F.); (P.S.); (M.L.S.); (K.D.M.); (V.G.); (F.C.)
| | - Cristiano Simone
- Medical Genetics, National Institute of Gastroenterology “S. de Bellis” Research Hospital, Castellana Grotte, 70013 Bari, Italy; (G.F.); (C.F.); (P.S.); (M.L.S.); (K.D.M.); (V.G.); (F.C.)
- Department of Biomedical Sciences and Human Oncology (DIMO), Medical Genetics, University of Bari Aldo Moro, 70124 Bari, Italy
- Correspondence: (V.D.); (C.S.)
| |
Collapse
|