UBC9 (E2) small ubiquitin-like modifier conjugating enzyme plays a key role in the post-translational modification of proteins named sumoylation. Defects in small ubiquitin-like modifier modification may contribute to breast carcinogenesis. In the present work, we examined UBC9 genetic variation.
UBC9 genetic variation was analyzed by using the high resolution melting (HRM) method. HRM study was conducted on 173-182 healthy women and 188-190 women with breast cancer.
During HRM screening, we analysed three known single-nucleotide polymorphisms in introns: rs4984806, rs909916 and rs909917, and one known single nucleotide polymorphism rs8063 in exon 7, in a non-coding region. The genotype frequencies for all polymorphisms were in accordance with Hardy - Weinberg equilibrium among the control subjects and breast cancer patients. The linkage disequilibrium analysis displayed that there was one polymorphism block, which consisted of three single nucleotide polymorphisms: rs909916, rs909917 and rs4984806. We identified two common haplotypes CCG and TTC, but we did not find significant differences in the distribution of these haplotypes between cases and controls.
Our study showed no differences in the occurrence of indicated polymorphisms in the UBC9 gene in a group of healthy women compared to women with breast cancer. These results suggest that the polymorphisms of the UBC9 gene - rs4984806, rs909916, rs909917 and rs8063 can be not associated with breast cancer risk.

The pattern of molecular evolution varies among gene sites and genes in a genome. By taking into account the complex heterogeneity of evolutionary processes among sites in a genome, Bayesian infinite mixture models of genomic evolution enable robust phylogenetic inference. With large modern data sets, however, the computational burden of Markov chain Monte Carlo sampling techniques becomes prohibitive. Here, we have developed a variational Bayesian procedure to speed up the widely used PhyloBayes MPI program, which deals with the heterogeneity of amino acid profiles. Rather than sampling from the posterior distribution, the procedure approximates the (unknown) posterior distribution using a manageable distribution called the variational distribution. The parameters in the variational distribution are estimated by minimizing Kullback-Leibler divergence. To examine performance, we analyzed three empirical data sets consisting of mitochondrial, plastid-encoded, and nuclear proteins. Our variational method accurately approximated the Bayesian inference of phylogenetic tree, mixture proportions, and the amino acid propensity of each component of the mixture while using orders of magnitude less computational time.

The majority of biomedical and biological research relies on a few molecular biology techniques. Here we show that eight key molecular biology techniques would not exist without basic biological research. We also find that the scientific reward system does not sufficiently value basic biological research into molecular mechanisms.

Since genetics has shown that mutation predates selection, biology has developed within the Darwinian paradigm framework. However, a mechanism that produces favorable mutations preferentially in response to adaptive constraints has been recently identified. This mechanism, the CRISPR-Cas adaptive immunity system, is considered as a bona fide example of Lamarckian evolution, even if it only reflects loosely Lamarck\'s ideas. This unusual evolutionary process is made possible by two prokaryotic properties: i) somatic and germinal cells are not distinct sets of cells; ii) Archae and Bacteria very frequently integrate DNA fragments from the environment, and they therefore have access to a source of \"ready-made\" useful genetic information. The CRISPR-Cas is a defense system against viruses and plasmids that is based on the integration of genomic fragments of these infectious agents into the host genome, and that protects the host against subsequent infections. Therefore, this mechanism does produce advantageous mutations by integrating DNA from the environment and allowing its transmission to descendants. In conclusion, most of the time evolution relies on purely Darwinian processes, i.e. mutations occurring at random, but in a small minority of cases the occurrence of mutations is more or less biased, and is therefore more or less Lamarckian. Although they are rare, such processes are nevertheless important to our understanding of the plurality of modes of evolution.

Hemoglobin SO-Arab is a rare sickling disorder with a clinical course similar to that of hemoglobin SS. Hemoglobin C-Harlem is another rare condition that produces sickling disorders in affected individuals with a disease course and electrophoretic findings similar to that of hemoglobin SO-Arab. The authors report the case of a 38-year-old African American man with hemoglobin SO-Arab and the challenges that may arise in working up a rare hemoglobinopathy.

BACKGROUND: Mariner elements represent the most successful family of autonomous DNA transposons, being present in various plant and animal genomes, including humans. The introduction and co-evolution of mariners within host genomes imply a strict regulation of the transposon activity. Biochemical data accumulated during the past decade have led to a convergent picture of the transposition cycle of mariner elements, suggesting that mariner transposition does not rely on host-specific factors. This model does not account for differences of transposition efficiency in human cells between mariners. We thus wondered whether apparent similarities in transposition cycle could hide differences in the intrinsic parameters that control mariner transposition.
RESULTS: We find that Mos1 transposase concentrations in excess to the Mos1 ends prevent the paired-end complex assembly. However, we observe that Mos1 transposition is not impaired by transposase high concentration, dismissing the idea that transposase over production plays an obligatory role in the down-regulation of mariner transposition. Our main finding is that the paired-end complex is formed in a cooperative way, regardless of the transposase concentration. We also show that an element framed by two identical ITRs (Inverted Terminal Repeats) is more efficient in driving transposition than an element framed by two different ITRs (i.e. the natural Mos1 copy), the latter being more sensitive to transposase concentration variations. Finally, we show that the current Mos1 ITRs correspond to the ancestral ones.
CONCLUSIONS: We provide new insights on intrinsic properties supporting the self-regulation of the Mos1 element. These properties (transposase specific activity, aggregation, ITR sequences, transposase concentration/transposon copy number ratio...) could have played a role in the dynamics of host-genomes invasion by Mos1, accounting (at least in part) for the current low copy number of Mos1 within host genomes.

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This protocol details the steps for data quality assessment and control that are typically carried out during case-control association studies. The steps described involve the identification and removal of DNA samples and markers that introduce bias. These critical steps are paramount to the success of a case-control study and are necessary before statistically testing for association. We describe how to use PLINK, a tool for handling SNP data, to perform assessments of failure rate per individual and per SNP and to assess the degree of relatedness between individuals. We also detail other quality-control procedures, including the use of SMARTPCA software for the identification of ancestral outliers. These platforms were selected because they are user-friendly, widely used and computationally efficient. Steps needed to detect and establish a disease association using case-control data are not discussed here. Issues concerning study design and marker selection in case-control studies have been discussed in our earlier protocols. This protocol, which is routinely used in our labs, should take approximately 8 h to complete.

Trichophyton rubrum is the most common dermatophyte isolated from human dermatophytosis. We present the mycological diagnosis algorithm and results in an onychomycosis case--tinea unguium. Biological samples have been inoculated on both usual and special culture media and incubated at both 30 degrees C and 37 degrees C for a period of fourteen days. Based on the macroscopic and microscopic characters and on the physiological and biochemical tests results, we identified a Trichophyton rubrum granular type dermatophyte. We are discussing phenotypic mycological diagnosis limits and molecular diagnostic benefits for rapid setting up of fungal therapy in order to avoid chronic mycosis and their complications.

Thirty-five percent of colorectal cancer (CRC) susceptibility is thought to be attributable to genetics, but only a small proportion of the cases (<6%) can be explained by highly penetrant mutations. The rest of the susceptibility could be explained by a number of low-penetrance variants following a polygenic model of inheritance. Genetic modeling in rodents has been a successful tool for the unraveling of the genetic basis of diseases. The investigation of mouse quantitative trait loci led to the discovery of 15 \"susceptibility to colorectal cancer\" (Scc) loci. Thus, we aimed to analyze the human-mouse syntenic regions defined by these Scc loci and select human candidate genes within. Twenty-one genes were chosen and their single-nucleotide polymorphisms were tested as possible low-penetrance variants predisposing to CRC risk. Our most strongly associated single-nucleotide polymorphism, rs954353, seems to be in the 5\' region of the CYR61 gene, which could implicate it in terms of the cis-regulation of the gene. CYR61 has been proposed as a connection point among signaling pathways and a probable marker for early CRC detection. However, we could not replicate the association. Despite our negative results, we believe that our candidate gene selection strategy could be quite useful in the future determination of variants predisposing to disease.