Publications by authors named "Rebecca A Barnetson"

Genome-wide association studies (GWAS) have identified ten loci harboring common variants that influence risk of developing colorectal cancer (CRC). To enhance the power to identify additional CRC risk loci, we conducted a meta-analysis of three GWAS from the UK which included a total of 3,334 affected individuals (cases) and 4,628 controls followed by multiple validation analyses including a total of 18,095 cases and 20,197 controls. We identified associations at four new CRC risk loci: 1q41 (rs6691170, odds ratio (OR) = 1.

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Background: Previous studies have shown that aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) lower colorectal cancer (CRC) risk. However, the lowest effective NSAID dose, treatment duration, and effects on survival are not defined. In a large population-based case-control study, we have explored the relationship between NSAID dose and duration, CRC risk and overall CRC-specific survival.

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Purpose: To date, genomewide association studies have identified 10 genetic loci associated with colorectal cancer (CRC) susceptibility. We hypothesized that these loci might also affect cancer survival.

Experimental Design: To determine whether single-nucleotide polymorphisms tagging these 10 loci influenced all-cause and CRC-specific mortality, we prospectively followed survival outcomes for 2,838 Scottish patients recruited soon after a diagnosis of CRC.

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Background: Germline mutations in MSH6 account for 10%-20% of Lynch syndrome colorectal cancers caused by hereditary DNA mismatch repair gene mutations. Because there have been only a few studies of mutation carriers, their cancer risks are uncertain.

Methods: We identified 113 families of MSH6 mutation carriers from five countries that we ascertained through family cancer clinics and population-based cancer registries.

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Mutations in the mitochondrial DNA (mtDNA) have been found to be present in several types of tumours including tumours of the large bowel. However, their role in cancer development and prognosis is still to be resolved. We used 2838 cases from a large Scottish colorectal cancer (CRC) case-control study to examine whether inherited genetic variation at the mtDNA influenced all-cause and CRC-specific mortality.

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Lynch Syndrome/HNPCC is a syndrome of cancer predisposition linked to inherited mutations of genes participating in post-replicative DNA mismatch repair (MMR). The spectrum of cancer associated with Lynch Syndrome includes tumours of the colorectum, endometrium, ovary, upper gastrointestinal tract and the urothelium although other cancers are rarely described. We describe a family of Lynch Syndrome with an hMLH1 mutation, that harbours an unusual tumour spectrum and its diagnostic and management challenges.

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Genome-wide association (GWA) studies have identified multiple loci at which common variants modestly influence the risk of developing colorectal cancer (CRC). To enhance power to identify additional loci with similar effect sizes, we conducted a meta-analysis of two GWA studies, comprising 13,315 individuals genotyped for 38,710 common tagging SNPs. We undertook replication testing in up to eight independent case-control series comprising 27,418 subjects.

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Vitamin D has anticarcinogenic properties and might influence colorectal cancer (CRC) risk, but the epidemiological evidence is inconsistent. Many mechanisms of action for vitamin D have been proposed, with some of them initiating via its binding to the vitamin D receptor (VDR). Using a large Scottish case-control study, we investigated (i) main associations between CRC, vitamin D and calcium dietary intake and 4 VDR single nucleotide polymorphisms (rs10735810, rs1544410, rs11568820, rs7975232) and (ii) interaction associations between the VDR variants, vitamin D and calcium intakes.

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In a large Scottish case-control study, we investigated the effects of adenomatous polyposis coli (APC) Asp1822Val (rs459552) and APC Glu1317Gln substitutions on colorectal cancer (CRC) risk and whether these associations were influenced by lifestyle and dietary factors. We did not observe any associations between the variants and CRC risk in the whole population. Post-menopausal women taking hormone replacement therapy (HRT) and participants who consumed a diet low in total fat, saturated fatty acids, monounsaturated fatty acids (MUFAs) and trans fatty acids had a lower risk of CRC [odds ratio (95% confidence interval): 0.

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To identify colorectal cancer (CRC) susceptibility alleles, we conducted a genome-wide association study. In phase 1, we genotyped 550,163 tagSNPs in 940 familial colorectal tumor cases (627 CRC, 313 high-risk adenoma) and 965 controls. In phase 2, we genotyped 42,708 selected SNPs in 2,873 CRC cases and 2,871 controls.

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In a genome-wide association study to identify loci associated with colorectal cancer (CRC) risk, we genotyped 555,510 SNPs in 1,012 early-onset Scottish CRC cases and 1,012 controls (phase 1). In phase 2, we genotyped the 15,008 highest-ranked SNPs in 2,057 Scottish cases and 2,111 controls. We then genotyped the five highest-ranked SNPs from the joint phase 1 and 2 analysis in 14,500 cases and 13,294 controls from seven populations, and identified a previously unreported association, rs3802842 on 11q23 (OR = 1.

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Vitamin B6, a coenzyme in the folate metabolism pathway, may have anticarcinogenic effects. Laboratory and epidemiologic studies support the hypothesis of its protective effect against colorectal cancer (CRC). The aim of this large Scottish case-control study, including 2,028 hospital-based cases and 2,722 population-based controls, was to investigate the associations between dietary and supplementary intake of vitamin B6 and CRC.

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Identification of germline mutations in DNA mismatch repair genes in colorectal cancer probands without an extensive family history can be problematic when ascribing relevance to cancer causation. We undertook a structured assessment of the disease-causing potential of sequence variants identified in a prospective, population-based study of 932 colorectal cancer patients, diagnosed at <55 years of age. Patient samples were screened for germline mutations in MLH1, MSH2, and MSH6.

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Background: The identification of mutations in germ-line DNA mismatch-repair genes at the time of diagnosis of colorectal cancer is important in the management of the disease.

Methods: Without preselection and regardless of family history, we recruited 870 patients under the age of 55 years soon after they received a diagnosis of colorectal cancer. We studied these patients for germ-line mutations in the DNA mismatch-repair genes MLH1, MSH2, and MSH6 and developed a two-stage model by multivariate logistic regression for the prediction of the presence of mutations in these genes.

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STK15 (Aurora-A) is a serine/threonine kinase involved in mitotic chromosomal segregation. A genetic variant in STK15 T+91A (resulting in the amino acid substitution F31I) is associated with increased aneuploidy in colon tumors and cell transformation in vitro. Since this polymorphism plays a role in mitotic control-a process critical for all cancer types-we conducted association analyses for risk of cancer development of the colon, breast, prostate, skin, lung and esophagus in 10 independent case-control populations.

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