Improvement in ACE I/D polymorphism detection

The ACE I/D polymorphism has been reported to influence predisposition to cardiovascular disease. Conflicting results in its detection may be due to mistyping of I/D genotypes as D/D genotypes occurring in the traditional genotyping method. In order to resolve mistyping troubles and to permit a rapid and accurate analysis, we performed a stepdown PCR reaction followed by detection using Nanogen technology, and we compared these results with those obtained from traditional genotyping methods, such as conventional and confirmatory PCR. The Nanogen stepdown method showed a 100% sensitivity and 99.6% specificity, when compared with the confirmatory PCR. Our experiments provide evidence that, by using the Nanogen stepdown method, the DD mistyping was markedly decreased, thus representing a useful tool suitable for performing large-scale screening or research

Enhanced copy number variants detection from whole-exome sequencing data using EXCAVATOR2

Copy Number Variants (CNVs) are structural rear- rangements contributing to phenotypic variation that have been proved to be associated with many dis- ease states. Over the last years, the identification of CNVs from whole-exome sequencing (WES) data has become a common practice for research and clinical purpose and, consequently, the demand for more and more efficient and accurate methods has increased. In this paper, we demonstrate that more than 30% of WES data map outside the targeted re- gions and that these reads, usually discarded, can be exploited to enhance the identification of CNVs from WES experiments. Here, we present EXCAVATOR2, the first read count based tool that exploits all the reads produced by WES experiments to detect CNVs with a genome-wide resolution. To evaluate the per- formance of our novel tool we use it for analysing two WES data sets, a population data set sequenced by the 1000 Genomes Project and a tumor data set made of bladder cancer samples. The results obtained from these analyses demonstrate that EXCAVATOR2 out- performs other four state-of-the-art methods and that our combined approach enlarge the spectrum of detectable CNVs from WES data with an unprece- dented resolution

Marfan syndrome: Current perspectives

Marfan syndrome (MFS) is a pleiotropic connective tissue disease inherited as an autosomal dominant trait, due to mutations in the FBN1 gene encoding fibrillin 1. It is an important protein of the extracellular matrix that contributes to the final structure of a microfibril. Few cases displaying an autosomal recessive transmission are reported in the world. The FBN1 gene, which is made of 66 exons, is located on chromosome 15q21.1. This review, after an introduction on the clinical manifestations that leads to the diagnosis of MFS, focuses on cardiovascular manifestations, pharmacological and surgical therapies of thoracic aortic aneurysm and/or dissection (TAAD), mechanisms underlying the progression of aneurysm or of acute dissection, and biomarkers associated with progression of TAADs. A Dutch group compared treatment with losartan, an angiotensin II receptor-1 blocker, vs no other additional treatment (COMPARE clinical trial). They observed that losartan reduces the aortic dilatation rate in patients with Marfan syndrome. Later on, they also reported that losartan exerts a beneficial effect on patients with Marfan syndrome carrying an FBN1 mutation that causes haploinsufficiency (quantitative mutation), while it has no significant effect on patients displaying dominant negative (qualitative) mutations. Moreover, a French group in a 3-year trial compared the administration of losartan vs placebo in patients with Marfan syndrome under treatment with beta-receptor blockers. They observed that losartan decreases blood pressure but has no effect on aortic diameter progression. Thus, beta-receptor blockers remain the gold standard therapy in patients with Marfan syndrome. Three potential biochemical markers are mentioned in this review: total homocysteine, serum transforming growth factor beta, and lysyl oxidase. Moreover, markers of oxidative stress measured in plasma, previously correlated with clinical features of Marfan syndrome, may be explored as potential biomarkers of clinical severity

Non-traumatic splenic rupture on dual antiplatelet therapy with aspirin and ticagrelor after stenting for acute coronary syndrome

AbstractWe report a case of non-traumatic splenic rupture in a 57-year-old man on dual antiplatelet therapy (DAPT) with aspirin and ticagrelor, seven months after percutaneous coronary intervention and drug-eluting stent implantation for non-ST elevation myocardial infarction. No splenic abnormalities were found at histopathological analysis after splenectomy, and no history of recent trauma was reported. Once restarted, DAPT after splenectomy, assessment of platelet function was performed by light transmittance aggregometry, showing a profound inhibition of platelet function by adenosine diphosphate, arachidonic acid, and collagen. Taking into account the bleeding risk associated with low on-treatment platelet reactivity, and to switch the patient from ticagrelor to a less potent P2Y12 inhibitor such as clopidogrel, cytochrome P450, genetic polymorphisms accounting for clopidogrel response variability were analyzed. The polymorphisms associated with lower response (CYP2C19*2, CYP2C19*3) were absent. Therefore, ticagrelor was withdrawn, and DAPT was continued with aspirin and clopidogrel. Rupture of the spleen may occur in the absence of major trauma or previous splenic diseases, and could be a complication of antithrombotic treatments. Moreover, low on-treatment platelet reactivity during DAPT is emerging as a possible risk factor for bleeding complications, so underlining the usefulness of assessing platelet function in special conditions to ensure that the patient receives the best tailored antiplatelet therapy.<Learning objective: Non-traumatic splenic rupture is a rare event, and is more often associated with pre-existing splenic abnormalities. However, it may be also a complication of medical treatments, especially with antithrombotic drugs. Low on-treatment platelet reactivity is emerging as a possible risk factor for bleeding complications; therefore, assessing platelet function in special conditions could be useful to ensure the patient receives the best-tailored antiplatelet therapy.