The value of MUTYH testing in patients with early onset microsatellite stable colorectal cancer referred for hereditary nonpolyposis colon cancer syndrome testing. Genet Test 2007;11(4):361-5
Date
02/26/2008Pubmed ID
18294051DOI
10.1089/gte.2007.0014Scopus ID
2-s2.0-38149085456 (requires institutional sign-in at Scopus site) 24 CitationsAbstract
MUTYH adenomatous polyposis (MAP) can mimic both the familial adenomatous polyposis (FAP) and hereditary nonpolyposis colon cancer (HNPCC) phenotypes. As a result of MAP's phenotypic overlap with FAP, some DNA diagnostic laboratories perform MUTYH testing in conjunction with APC testing in patients with suspected FAP or attenuated FAP (AFAP). In addition to testing FAP/AFAP samples for MUTYH mutations, we were interested whether there would also be value in testing samples referred for HNPCC testing. To determine this, we tested a consecutive series of 229 samples referred for HNPCC testing for the two most common MUTYH mutations in the Caucasian population. To enrich our study population with MAP cases, we only included samples from patients with early onset colorectal cancer (CRC diagnosed <50 years old) in whom HNPCC had been excluded by microsatellite instability testing (microsatellite stable or low microsatellite instability). Four biallelic (2%) and six monoallelic (3%) MUTYH mutation carriers were identified. No clinical factors predicted MUTYH mutation status. Specifically, a family history of vertical transmission of CRC or having few polyps (<15) did not rule out the possibility of biallelic MUTYH mutations. Thus, MUTYH mutation testing may be a reasonable cascade test in early onset CRC found to have proficient DNA mismatch repair, regardless of pattern of family history or number of polyps.
Author List
Riegert-Johnson DL, Johnson RA, Rabe KG, Wang L, Thomas B, Baudhuin LM, Thibodeau SN, Boardman LAMESH terms used to index this publication - Major topics in bold
AdultAge of Onset
Colorectal Neoplasms
Colorectal Neoplasms, Hereditary Nonpolyposis
DNA Glycosylases
DNA Mutational Analysis
Female
Genetic Predisposition to Disease
Genotype
Humans
Male
Microsatellite Instability
Middle Aged
Syndrome
