BACKGROUND & AIMS: Biallelic mutations in the base-excision repair gene MYH have recently been associated with recessive inheritance of multiple colorectal adenomas. An investigation and characterization of MYH mutations in Swedish patients were therefore carried out. METHODS: A set of 15 unrelated adenomatous polyposis coli (APC)-mutation negative patients from the Swedish Polyposis Registry was screened for germline mutations in the MYH gene. The patients were clinically characterized and compared with 43 APC-mutation positive probands diagnosed during the same period. RESULTS: Disease-causing biallelic MYH mutations were identified in 6 patients (40%). The mean age at diagnosis was 47.8 years versus 34.1 years in APC-mutation positive patients (P = .015). Colorectal cancer at diagnosis of polyposis was present in 67% (4/6) of the patients, and all were right-sided, compared with only 19% versus 12.5% right-sided cancer in APC-mutation positive patients. Upper gastrointestinal manifestations were diagnosed in 1 of 5 compared with 23 of 27 in APC-mutation positive patients (odds ratio, 23; 95% confidence interval, 2-263; P = .0086). One family exhibited apparent dominant inheritance of colorectal adenomatous polyposis. Two new pathogenic mutations, MYH p.G175E and p.P391L, were identified. The mutations are argued to introduce profound changes in substrate-recognizing domains of the protein. CONCLUSIONS: Biallelic MYH mutations, including 2 novel mutations, were found in a substantial number of the patients with multiple colorectal adenomas who were negative for APC-mutation. The examined MYH-mutation positive patients were found to have higher risks of colorectal cancer at diagnosis, right-sided location of cancers, and a significantly lower incidence of upper gastrointestinal manifestations, compared with APC-mutation positive patients.
BACKGROUND & AIMS: Biallelic mutations in the base-excision repair gene MYH have recently been associated with recessive inheritance of multiple colorectal adenomas. An investigation and characterization of MYH mutations in Swedish patients were therefore carried out. METHODS: A set of 15 unrelated adenomatous polyposis coli (APC)-mutation negative patients from the Swedish Polyposis Registry was screened for germline mutations in the MYH gene. The patients were clinically characterized and compared with 43 APC-mutation positive probands diagnosed during the same period. RESULTS: Disease-causing biallelic MYH mutations were identified in 6 patients (40%). The mean age at diagnosis was 47.8 years versus 34.1 years in APC-mutation positive patients (P = .015). Colorectal cancer at diagnosis of polyposis was present in 67% (4/6) of the patients, and all were right-sided, compared with only 19% versus 12.5% right-sided cancer in APC-mutation positive patients. Upper gastrointestinal manifestations were diagnosed in 1 of 5 compared with 23 of 27 in APC-mutation positive patients (odds ratio, 23; 95% confidence interval, 2-263; P = .0086). One family exhibited apparent dominant inheritance of colorectal adenomatous polyposis. Two new pathogenic mutations, MYHp.G175E and p.P391L, were identified. The mutations are argued to introduce profound changes in substrate-recognizing domains of the protein. CONCLUSIONS: Biallelic MYH mutations, including 2 novel mutations, were found in a substantial number of the patients with multiple colorectal adenomas who were negative for APC-mutation. The examined MYH-mutation positive patients were found to have higher risks of colorectal cancer at diagnosis, right-sided location of cancers, and a significantly lower incidence of upper gastrointestinal manifestations, compared with APC-mutation positive patients.
Authors: Aung Ko Win; Sean P Cleary; James G Dowty; John A Baron; Joanne P Young; Daniel D Buchanan; Melissa C Southey; Terrilea Burnett; Patrick S Parfrey; Roger C Green; Loïc Le Marchand; Polly A Newcomb; Robert W Haile; Noralane M Lindor; John L Hopper; Steven Gallinger; Mark A Jenkins Journal: Int J Cancer Date: 2011-04-08 Impact factor: 7.396
Authors: Jun Li; Susan L Woods; Sue Healey; Jonathan Beesley; Xiaoqing Chen; Jason S Lee; Haran Sivakumaran; Nicci Wayte; Katia Nones; Joshua J Waterfall; John Pearson; Anne-Marie Patch; Janine Senz; Manuel A Ferreira; Pardeep Kaurah; Robertson Mackenzie; Alireza Heravi-Moussavi; Samantha Hansford; Tamsin R M Lannagan; Amanda B Spurdle; Peter T Simpson; Leonard da Silva; Sunil R Lakhani; Andrew D Clouston; Mark Bettington; Florian Grimpen; Rita A Busuttil; Natasha Di Costanzo; Alex Boussioutas; Marie Jeanjean; George Chong; Aurélie Fabre; Sylviane Olschwang; Geoffrey J Faulkner; Evangelos Bellos; Lachlan Coin; Kevin Rioux; Oliver F Bathe; Xiaogang Wen; Hilary C Martin; Deborah W Neklason; Sean R Davis; Robert L Walker; Kathleen A Calzone; Itzhak Avital; Theo Heller; Christopher Koh; Marbin Pineda; Udo Rudloff; Martha Quezado; Pavel N Pichurin; Peter J Hulick; Scott M Weissman; Anna Newlin; Wendy S Rubinstein; Jone E Sampson; Kelly Hamman; David Goldgar; Nicola Poplawski; Kerry Phillips; Lyn Schofield; Jacqueline Armstrong; Cathy Kiraly-Borri; Graeme K Suthers; David G Huntsman; William D Foulkes; Fatima Carneiro; Noralane M Lindor; Stacey L Edwards; Juliet D French; Nicola Waddell; Paul S Meltzer; Daniel L Worthley; Kasmintan A Schrader; Georgia Chenevix-Trench Journal: Am J Hum Genet Date: 2016-04-14 Impact factor: 11.025
Authors: A M O'Shea; S P Cleary; M A Croitoru; H Kim; T Berk; N Monga; R H Riddell; A Pollett; S Gallinger Journal: Histopathology Date: 2008-06-28 Impact factor: 5.087