Background: The CpG island methylator phenotype (CIMP) represents a subset of colorectal cancers characterized by widespread aberrant DNA hypermethylation at select CpG islands. The risk factors and environmental exposures contributing to etiologic heterogeneity between CIMP and non-CIMP tumors are not known.
Methods: We measured the CIMP status of 3,119 primary population-based colorectal cancer tumors from the multinational Colon Cancer Family Registry.
A recent two-stage genome-wide association study (GWAS) identified five novel breast cancer susceptibility loci on chromosomes 9, 10, and 11. To provide more reliable estimates of the relative risk associated with these loci and investigate possible heterogeneity by subtype of breast cancer, we genotyped the variants rs2380205, rs1011970, rs704010, rs614367, and rs10995190 in 39 studies from the Breast Cancer Association Consortium (BCAC), involving 49,608 cases and 48,772 controls of predominantly European ancestry. Four of the variants showed clear evidence of association (P ≤ 3 × 10(-9) ) and weak evidence was observed for rs2380205 (P = 0.
View Article and Find Full Text PDFAccording to recently published guidelines, microsatellite instability (MSI) testing of colorectal cancers may be clinically indicated on a significant proportion of all colorectal tumors. To date, nothing has been published regarding the reproducibility of MSI testing between laboratories. We present MSI quality control activities experience of a six center multinational consortium, as laboratories developed competency with MSI testing and interpretation.
View Article and Find Full Text PDFThe MutY human homologue (MYH) gene encodes a member of the base excision repair pathway that is involved in repairing oxidative damage to DNA. Two germline MYH gene mutations that result in Myh proteins containing amino acid substitutions Y165C and G382D (hereafter called the Y165C and G382D mutations) are associated with adenomatous poly-posis and colorectal cancer among patients from several European poly-posis registries. We used a population-based series of 1238 colorectal cancer patients and 1255 healthy control subjects from Ontario, Canada, to examine the risk of colorectal cancer among biallelic and monoallelic germline MYH Y165C and G382D mutation carriers.
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