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BackgroundWorldwide, grapes and their derived products have a large market. The cultivated grape species Vitis vinifera has potential to become a model for fruit trees genetics. Like many plant species, it is highly heterozygous, which is an additional challenge to modern whole genome shotgun sequencing. In this paper a high quality draft genome sequence of a cultivated clone of V. vinifera Pinot Noir is presented.Principal FindingsWe estimate the genome size of V. vinifera to be 504.6 Mb. Genomic sequences corresponding to 477.1 Mb were assembled in 2,093 metacontigs and 435.1 Mb were anchored to the 19 linkage groups (LGs). The number of predicted genes is 29,585, of which 96.1% were assigned to LGs. This assembly of the grape genome provides candidate genes implicated in traits relevant to grapevine cultivation, such as those influencing wine quality, via secondary metabolites, and those connected with the extreme susceptibility of grape to pathogens. Single nucleotide polymorphism (SNP) distribution was consistent with a diffuse haplotype structure across the genome. Of around 2,000,000 SNPs, 1,751,176 were mapped to chromosomes and one or more of them were identified in 86.7% of anchored genes. The relative age of grape duplicated genes was estimated and this made possible to reveal a relatively recent Vitis-specific large scale duplication event concerning at least 10 chromosomes (duplication not reported before).ConclusionsSanger shotgun sequencing and highly efficient sequencing by synthesis (SBS), together with dedicated assembly programs, resolved a complex heterozygous genome. A consensus sequence of the genome and a set of mapped marker loci were generated. Homologous chromosomes of Pinot Noir differ by 11.2% of their DNA (hemizygous DNA plus chromosomal gaps). SNP markers are offered as a tool with the potential of introducing a new era in the molecular breeding of grape.

Purpose: BRCA1/2-mutated and some sporadic triple-negative breast cancers (TNBC) have DNA repair defects and are sensitive to DNA-damaging therapeutics. Recently, three independent DNA-based measures of genomic instability were developed on the basis of loss of heterozygosity (LOH), telomeric allelic imbalance (TAI), and large-scale state transitions (LST).Experimental Design: We assessed a combined homologous recombination deficiency (HRD) score, an unweighted sum of LOH, TAI, and LST scores, in three neoadjuvant TNBC trials of platinum-containing therapy. We then tested the association of HR deficiency, defined as HRD score !42 or BRCA1/2 mutation, with response to platinum-based therapy.

SUMMARY Background Optimal management of clinically localized prostate cancer presents unique challenges because of its highly variable and often indolent natural history. To predict disease aggressiveness, clinicians combine clinical parameters to create prognostic models, but the accuracy of current models is very limited. There is significant clinical need for biomarkers that improve our ability to predict disease outcome. Methods Using quantitative RT-PCR on RNA from formalin fixed paraffin-embedded tumour samples, we measured the expression level of 31 genes involved in cell cycle progression (CCP genes), created a predefined score and evaluated its ability to predict disease outcome. The signature was tested in a retrospective cohort of 366 patients from the U.S. who had undergone radical prostatectomy, and in a retrospective cohort of 337 men with clinically localized prostate cancer diagnosed by a transurethral resection (TURP) in the UK and managed conservatively. Findings The cell cycle progression signature was a highly significant predictor of outcome in both cohorts. After prostatectomy the CCP score predicted biochemical recurrence in univariate (Hazard ratio (HR) for a one unit change in CCP (doubling) = 1.89; 95% CI (1.54, 2.31) χ2 = 34·0, 1df, p = 5·6 × 10−9) and multivariate analysis (HR = 1.74; 95% CI (1.39, 2.17) χ2 = 21·65, 1df, p = 3·3 ×10−6). The CCP score and PSA were the dominant variables in the best predictive model and were much more significant than any other clinical measure. In the TURP cohort, the CCP score was the dominant variable for predicting death from prostate cancer in both univariate (HR= 2.92; 95% CI (2.38, 3.57) χ2 = 92·7, 1df, p = 6.1 × 10−22) and multivariate analyses (χ2 = 42·2, p = 8·2 × 10−11), where it was much stronger than all other prognostic factors. In no case 4 was there significant evidence for heterogeneity in the hazard ratio for the CCP score across any clinical parameter. Interpretation The CCP score provides a substantial amount of independent information about the risk of recurrence after radical prostatectomy and the risk of death in conservatively managed prostate cancer diagnosed by TURP. Taken together, these studies provide strong evidence that the CCP score is a highly robust prognostic marker which, after additional validation, could have a central role in determining appropriate treatment for prostate cancer patients. Funding Study funded by Cancer Research UK, the Orchid Appeal, US National Institutes of Health (SPORE CA92629), and the Koch Foundation. Molecular testing performed at Myriad Genetics.

Germline mutations in BRCA1/2 predispose individuals to breast cancer (termed germline-mutated BRCA1/2 breast cancer, gBRCA-BC) by impairing homologous recombination (HR) and causing genomic instability. HR also repairs DNA lesions caused by platinum agents and PARP inhibitors. Triple-negative breast cancers (TNBCs) harbor subpopulations with BRCA1/2 mutations, hypothesized to be especially platinum-sensitive. Cancers in putative 'BRCAness' subgroups-tumors with BRCA1 methylation; low levels of BRCA1 mRNA (BRCA1 mRNA-low); or mutational signatures for HR deficiency and those with basal phenotypes-may also be sensitive to platinum. We assessed the efficacy of carboplatin and another mechanistically distinct therapy, docetaxel, in a phase 3 trial in subjects with unselected advanced TNBC. A prespecified protocol enabled biomarker-treatment interaction analyses in gBRCA-BC and BRCAness subgroups. The primary endpoint was objective response rate (ORR). In the unselected population (376 subjects; 188 carboplatin, 188 docetaxel), carboplatin was not more active than docetaxel (ORR, 31.4% versus 34.0%, respectively; P = 0.66). In contrast, in subjects with gBRCA-BC, carboplatin had double the ORR of docetaxel (68% versus 33%, respectively; biomarker, treatment interaction P = 0.01). Such benefit was not observed for subjects with BRCA1 methylation, BRCA1 mRNA-low tumors or a high score in a Myriad HRD assay. Significant interaction between treatment and the basal-like subtype was driven by high docetaxel response in the nonbasal subgroup. We conclude that patients with advanced TNBC benefit from characterization of BRCA1/2 mutations, but not BRCA1 methylation or Myriad HRD analyses, to inform choices on platinum-based chemotherapy. Additionally, gene expression analysis of basal-like cancers may also influence treatment selection.