Common variation at 6p21.31 (BAK1) influences the risk of chronic lymphocytic leukemia.

We performed a meta-analysis of 3 genome-wide association studies to identify additional common variants influencing chronic lymphocytic leukemia (CLL) risk. The discovery phase was composed of genome-wide association study data from 1121 cases and 3745 controls. Replication analysis was performed in 861 cases and 2033 controls. We identified a novel CLL risk locus at 6p21.33 (rs210142; intronic to the BAK1 gene, BCL2 antagonist killer 1; P = 9.47 × 10(-16)). A strong relationship between risk genotype and reduced BAK1 expression was shown in lymphoblastoid cell lines. This finding provides additional support for polygenic inheritance to CLL and provides further insight into the biologic basis of disease development.

Chromosome 7p11.2 (EGFR) variation influences glioma risk.

While gliomas are the most common primary brain tumors, their etiology is largely unknown. To identify novel risk loci for glioma, we conducted genome-wide association (GWA) analysis of two case-control series from France and Germany (2269 cases and 2500 controls). Pooling these data with previously reported UK and US GWA studies provided data on 4147 glioma cases and 7435 controls genotyped for 424 460 common tagging single-nucleotide polymorphisms. Using these data, we demonstrate two statistically independent associations between glioma and rs11979158 and rs2252586, at 7p11.2 which encompasses the EGFR gene (population-corrected statistics, P(c) = 7.72 × 10(-8) and 2.09 × 10(-8), respectively). Both associations were independent of tumor subtype, and were independent of EGFR amplification, p16INK4a deletion and IDH1 mutation status in tumors; compatible with driver effects of the variants on glioma development. These findings show that variation in 7p11.2 is a determinant of inherited glioma risk.

rs2072135, a low-penetrance variant for chronic lymphocytic leukaemia?

Recent multi-stage genome-wide association studies (GWAS) have identified single nucleotide polymorphisms (SNPs) that are robustly associated with chronic lymphocytic leukaemia (CLL) risk. Given that most of these SNPs map to non-coding regions of the genome, it suggests that the functional basis of many GWAS signals will be through differential gene expression. By referencing publically accessible expression quantitative trait loci (eQTL) data on lymphoblastoid cells lines (LCLs) we have globally demonstrated an association between GWAS P-values and eQTLs, consistent with much of the variation in CLL risk being defined by variants impacting on gene expression. To explore using eQTL data to select GWAS SNPs for replication, we genotyped rs2072135 (GWAS P-value = 0·0024, eQTL P-value = 1·510(-19)) in five independent case-control series totalling 1968 cases and 3538 controls. While not attaining statistical significance (combined P-value = 1 × 10(-4)), rs2072135 defines a promising risk locus for CLL. Incorporating eQTL information offers an attractive strategy for selecting SNPs from GWAS for validation.

Comprehensive evaluation of the impact of 14 genetic variants on colorectal cancer phenotype and risk.

To comprehensively evaluate the impact of recently identified colorectal cancer (CRC) variants at 1q41, 3q26.2, 8q23.3, 8q24.21, 10p14, 11q23.1, 12q13.13, 14q22.2, 15q13.3, 16q22.1, 18q21.1, 19q13.11, 20p12.3, and 20q13.33 on risk and CRC phenotype, the authors analyzed 8,878 cases and 6,051 controls from the United Kingdom ascertained in 1999-2007. The impact of variants on the familial CRC risk was enumerated from age-, sex-, and calendar-specific CRC rates in the 50,924 first-degree relatives of cases. Each of the 14 susceptibility loci independently influences CRC with the risk increasing with increasing number of risk alleles carried (per allele odds ratio = 1.13; P = 2.99 × 10(-58)) and, for those within the upper quintile, there is a 2.3-fold increased risk. In first-degree relatives of cases with ≤17, 18-21, and ≥22 risk alleles, standardized incidence ratios were 1.76, 2.08, and 2.25, respectively. Although the discriminatory attributes of the 14 CRC susceptibility loci for individual risk prediction are poor (area under the curve = 0.58), they may allow subgroups of the population at different CRC risks to be distinguished.

Common genetic variation at 15q25.2 impacts on chronic lymphocytic leukaemia risk.

A genome-wide association study of chronic lymphocytic leukaemia (CLL) suggested that common variants at 15q25.2 (rs783540) and 18q21.1 (rs1036935) influence CLL. To validate these associations and explore their relationship with CLL risk we genotyped case-control datasets from Poland, UK and Italy totalling 1428 cases and 1920 controls. Combined data from these and previously genotyped series (2503 cases and 5789 controls) provided evidence for an association between 15q25.2 and 18q21.1 loci and CLL risk (P(combined) = 1·10 × 10(-7) and 1·30 × 10(-5) respectively). These data provide further evidence for the involvement of common genetic variants in CLL risk and insight into the biological basis of disease development.

Association between single nucleotide polymorphism-genotype and outcome of patients with chronic lymphocytic leukemia in a randomized chemotherapy trial.

BACKGROUND: There is variability in the outcome of patients with chronic lymphocytic leukemia with apparently the same stage of disease. Identifying genetic variants that influence patients' outcome and response to treatment may provide important insights into the biology of the disease. DESIGN AND METHODS: We investigated the possibility that genetic variation influences outcome by conducting a genome-wide analysis of 346,831 single nucleotide polymorphisms in 356 patients entered into a phase III trial comparing the efficacy of fludarabine, chlorambucil, and fludarabine with cyclophosphamide as first-line treatment. Genotypes were linked to individual patients' outcome data and response to chemotherapy. The association between genotype and progression-free survival was assessed by Cox regression analysis adjusting for treatment and clinicopathology. RESULTS: The strongest associations were shown for rs1949733 (ACOX3; P=8.22x10-7), rs1342899 (P=7.72×10(-7)) and rs11158493 (PPP2R5E; P=8.50×10(-7)). In addition, the 52 single nucleotide polymorphisms associated at P<10(-4) included rs438034 (CENPF; P=4.86×10(-6)), previously correlated with cancer progression, and rs2255235 (B2M; P=3.10×10(-5)) and rs2064501 (IL22RA2; P=4.81×10(-5)) which map to B-cell genes. CONCLUSIONS: Our findings provide evidence that genetic variation is a determinant of progression-free survival of patients with chronic lymphocytic leukemia. Specific associations warrant further analyses.

Refinement of the basis and impact of common 11q23.1 variation to the risk of developing colorectal cancer.

The common single-nucleotide polymorphism (SNP) rs3802842 at 11q23.1 has recently been reported to be associated with risk of colorectal cancer (CRC). To examine this association in detail we genotyped rs3802842 in eight independent case-control series comprising a total of 10 638 cases and 10 457 healthy individuals. A significant association between the C allele of rs3802842 and CRC risk was found (per allele OR = 1.17; 95% confidence interval [CI]: 1.12-1.22; P = 1.08 x 10(-12)) with the risk allele more frequent in rectal than colonic disease (P = 0.02). In combination with 8q21, 8q24, 10p14, 11q, 15q13.3 and 18q21 variants, the risk of CRC increases with an increasing numbers of variant alleles for the six loci (OR(per allele) = 1.19; 95% CI: 1.15-1.23; P(trend) = 7.4 x 10(-24)). Using the data from our genome-wide association study of CRC, LD mapping and imputation, we were able to refine the location of the causal locus to a 60 kb region and screened for coding changes. The absence of exonic mutations in any of the transcripts (FLJ45803, LOC120376, C11orf53 and POU2AF1) mapping to this region makes the association likely to be a consequence of non-coding effects on gene expression.

A genome-wide association study identifies multiple susceptibility loci for chronic lymphocytic leukemia.

Genome-wide association studies (GWAS) of chronic lymphocytic leukemia (CLL) have shown that common genetic variation contributes to the heritable risk of CLL. To identify additional CLL susceptibility loci, we conducted a GWAS and performed a meta-analysis with a published GWAS totaling 1,739 individuals with CLL (cases) and 5,199 controls with validation in an additional 1,144 cases and 3,151 controls. A combined analysis identified new susceptibility loci mapping to 3q26.2 (rs10936599, P = 1.74 × 10(-9)), 4q26 (rs6858698, P = 3.07 × 10(-9)), 6q25.2 (IPCEF1, rs2236256, P = 1.50 × 10(-10)) and 7q31.33 (POT1, rs17246404, P = 3.40 × 10(-8)). Additionally, we identified a promising association at 5p15.33 (CLPTM1L, rs31490, P = 1.72 × 10(-7)) and validated recently reported putative associations at 5p15.33 (TERT, rs10069690, P = 1.12 × 10(-10)) and 8q22.3 (rs2511714, P = 2.90 × 10(-9)). These findings provide further insights into the genetic and biological basis of inherited genetic susceptibility to CLL.

Low-penetrance susceptibility variants in familial colorectal cancer.

BACKGROUND: Genomewide association studies have identified 10 low-penetrance loci that confer modestly increased risk for colorectal cancer (CRC). Although they underlie a significant proportion of CRC in the general population, their impact on the familial risk for CRC has yet to be formally enumerated. The aim of this study was to examine the combined contribution of the 10 variants, rs6983267, rs4779584, rs4939827, rs16892766, rs10795668, rs3802842, rs4444235, rs9929218, rs10411210, and rs961253, on familial CRC. METHODS: The population-based series of CRC samples included in this study consisted of 97 familial cases and 691 sporadic cases. Genotypes in the 10 loci and clinical data, including family history of cancer verified from the Finnish Cancer Registry, were available. The overall number of risk alleles (0-20) was determined, and its association with familial CRC was analyzed. Excess familial risk was estimated using cancer incidence data from the first-degree relatives of the cases. RESULTS: A linear association between the number of risk alleles and familial CRC was observed (P = 0.006). With each risk-allele addition, the odds of having an affected first-degree relative increased by 1.16 (95% confidence interval, 1.04-1.30). The 10 low-penetrance loci collectively explain approximately 9% of the variance in familial risk for CRC. CONCLUSIONS: This study provides evidence to support the previous indirect estimations that these low-penetrance variants account for a relatively small proportion of the familial aggregation of CRC. IMPACT: Our results emphasize the need to characterize the remaining molecular basis of familial CRC, which should eventually yield in individualized targeting of preventive interventions.

Common variants at 2q37.3, 8q24.21, 15q21.3 and 16q24.1 influence chronic lymphocytic leukemia risk.

To identify new risk variants for chronic lymphocytic leukemia (CLL), we conducted a genome-wide association study of 299,983 tagging SNPs, with validation in four additional series totaling 2,503 cases and 5,789 controls. We identified four new risk loci for CLL at 2q37.3 (rs757978, FARP2; odds ratio (OR) = 1.39; P = 2.11 x 10(-9)), 8q24.21 (rs2456449; OR = 1.26; P = 7.84 x 10(-10)), 15q21.3 (rs7169431; OR = 1.36; P = 4.74 x 10(-7)) and 16q24.1 (rs305061; OR = 1.22; P = 3.60 x 10(-7)). We also found evidence for risk loci at 15q25.2 (rs783540, CPEB1; OR = 1.18; P = 3.67 x 10(-6)) and 18q21.1 (rs1036935; OR = 1.22; P = 2.28 x 10(-6)). These data provide further evidence for genetic susceptibility to this B-cell hematological malignancy.

Plasminogen activator inhibitor variants PAI-1 A15T and PAI-2 S413C influence lung cancer prognosis.

The plasminogen pathway plays an important role in the behavior of many tumors including lung cancer. Hence genetic variants encoding plasminogen activator (PLAU), plasminogen receptor (PLAUR), plasminogen activator inhibitor 1 (PAI-1) and plasminogen activator inhibitor 2 (PAI-2) may contribute to lung cancer prognosis. To investigate this proposition we genotyped PAI-1 A15T, PLAU L141P, PLAUR L317P and PAI-2 S413C variants in 698 patients with lung cancer, 522 with non-small cell (NSCLC) and 176 with small cell lung cancer (SCLC). PAI-1 A15T was significantly associated with overall survival (OS), with carriers of variant alleles having a worse prognosis (hazard ratio (HR)=1.14; 95% confidence interval [CI]: 1.03-1.26). An association was also detected between OS in NSCLC and carrier status for PAI-2 413C (HR=1.13; 95% CI: 1.01-1.24). These common genetic variants identified warrant further evaluation as promising prognostic markers of patient outcome.

Clinical implications of the colorectal cancer risk associated with MUTYH mutation.

PURPOSE: Biallelic mutations in the base excision DNA repair gene MUTYH predispose to colorectal cancer (CRC). Evidence that monoallelic mutations also confer an elevated CRC risk is controversial. Precise quantification of the CRC risk and the phenotype associated with MUTYH mutations is relevant to the counseling, surveillance, and clinical management of at-risk individuals. METHODS: We analyzed a population-based series of 9,268 patients with CRC and 5,064 controls for the Y179C and G396D MUTYH mutations. We related genotypes to phenotype and calculated genotype-specific CRC risks. RESULTS: Overall, biallelic mutation status conferred a 28-fold increase in CRC risk (95% CI,17.66 to 44.06); this accounted for 0.3% of CRCs in the cohort. Genotype relative risks of CRC were strongly age dependent, but penetrance was incomplete at age 60 years. CRC that developed in the context of biallelic mutations were microsatellite stable. Biallelic mutation carriers were more likely to have proximal CRC (P = 4.0 x 10(-4)) and synchronous polyps (P = 5.7 x 10(-9)) than noncarriers. The performance characteristics of clinicopathologic criteria for the identification of biallelic mutations are poor. Monoallelic mutation was not associated with an increased CRC risk (odds ratio, 1.07; 95% CI, 0.87 to 1.31). CONCLUSION: The high risk and the propensity for proximal disease associated with biallielic MUTYH mutation justify colonoscopic surveillance. Although mutation screening should be directed to patients with APC-negative polyposis and early-onset proximal MSS CRC in whom detection rates will be highest, the expanded phenotype associated with MUTYH mutation needs to be recognized. There is no evidence than monoallelic mutation status per se is clinically important.

A genome-wide association study identifies six susceptibility loci for chronic lymphocytic leukemia.

We conducted a genome-wide association study of 299,983 tagging SNPs for chronic lymphocytic leukemia (CLL) and performed validation in two additional series totaling 1,529 cases and 3,115 controls. We identified six previously unreported CLL risk loci at 2q13 (rs17483466; P = 2.36 x 10(-10)), 2q37.1 (rs13397985, SP140; P = 5.40 x 10(-10)), 6p25.3 (rs872071, IRF4; P = 1.91 x 10(-20)), 11q24.1 (rs735665; P = 3.78 x 10(-12)), 15q23 (rs7176508; P = 4.54 x 10(-12)) and 19q13.32 (rs11083846, PRKD2; P = 3.96 x 10(-9)). These data provide the first evidence for the existence of common, low-penetrance susceptibility to a hematological malignancy and new insights into disease causation in CLL.

Meta-analysis of genome-wide association data identifies four new susceptibility loci for colorectal cancer.

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. We identified four previously unreported CRC risk loci at 14q22.2 (rs4444235, BMP4; P = 8.1 x 10(-10)), 16q22.1 (rs9929218, CDH1; P = 1.2 x 10(-8)), 19q13.1 (rs10411210, RHPN2; P = 4.6 x 10(-9)) and 20p12.3 (rs961253; P = 2.0 x 10(-10)). These findings underscore the value of large sample series for discovery and follow-up of genetic variants contributing to the etiology of CRC.

Clustering of individuals given SNPs similarity based on normalized mutual information: F7 SNPs in the GAIT sample.

This paper proposes the clustering of individuals given their genotype using a normalized Mutual Information dissimilarity distance. This method is applied to a Single Nucleotyde Polymorphism set belonging to F7 gene, uncovering the intrinsic genetic variability on one Spanish population. This genetic variability corresponds to results published using a complete different approach in population genetics literature. Identified groups are shown to express significant differences in the level of FVII concentration.