Improvement in the clinical outcome of human cancers requires characterization of the genetic alterations underlying their pathogenesis. Large-scale genomic and transcriptomic characterization of papillary thyroid carcinomas (PTCs) in Western populations has revealed multiple oncogenic drivers which are essential for understanding pathogenic mechanisms of this disease, while, so far, the genetic landscape in Chinese patients with PTC remains uncharacterized. Here, we conducted a large-scale genetic analysis of PTCs from patients in China to determine the mutational landscape of this cancer. By performing targeted DNA amplicon and targeted RNA deep-sequencing, we elucidated the landscape of somatic genetic alterations in 355 Chinese patients with PTC. A total of 88.7% of PTCs were found to harbor at least one candidate oncogenic driver genetic alteration. Among them, around 72.4% of the cases carried BRAF mutations; 2.8% of cases harbored RAS mutations; and 13.8% of cases were characterized with in-frame gene fusions, including seven newly identified kinase gene fusions. TERT promoter mutations were likely to occur in a sub-clonal manner in our PTC cohort. The prevalence of somatic genetic alterations in PTC was significantly different between our Chinese cohort and TCGA datasets for American patients. Additionally, combined analyses of genetic alterations and clinicopathologic features demonstrated that kinase gene fusion was associated with younger age at diagnosis, larger tumor size, and lymph node metastasis in PTC. With the analyses of DNA rearrangement sites of RET gene fusions in PTC, signatures of chromosome translocations related to RET fusion events were also depicted. Collectively, our results provide fundamental insight into the pathogenesis of PTC in the Chinese population. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley& Sons, Ltd.

Autism spectrum disorders (ASDs) are common neurodevelopmental disorders with a strong genetic etiology. However, due to the extreme genetic heterogeneity of ASDs, traditional approaches for gene discovery are challenging. Next-generation sequencing technologies offer an opportunity to accelerate the identification of the genetic causes of ASDs. Here, we report the results of whole-exome sequence in a cohort of 20 ASD patients. By extensive bioinformatic analysis, we identified novel mutations in seven genes that are implicated in synaptic function and neurodevelopment. After sequencing an additional 47 ASD samples, we identified three different missense mutations in ANK3 in four unrelated ASD patients, one of which, c.4705T>G (p.S1569A), is a de novo mutation. Given the fact that ANK3 has been shown to strongly associate with schizophrenia and bipolar disorder, our findings support an association between ANK3 mutations and ASD susceptibility and imply a shared molecular pathophysiology between ASDs and other neuropsychiatric disorders.

Murine rodents are excellent models for study of adaptive radiations and speciation. Brown Norway rats (Rattus norvegicus) are successful global colonizers and the contributions of their domesticated laboratory strains to biomedical research are well established. To identify nucleotide-based speciation timing of the rat and genomic information contributing to its colonization capabilities, we analyzed 51 whole-genome sequences of wild-derived Brown Norway rats and their sibling species, R. nitidus, and identified over 20 million genetic variants in the wild Brown Norway rats that were absent in the laboratory strains, which substantially expand the reservoir of rat genetic diversity. We showed that divergence of the rat and its siblings coincided with drastic climatic changes that occurred during the Middle Pleistocene. Further, we revealed that there was a geographically widespread influx of genes between Brown Norway rats and the sibling species following the divergence, resulting in numerous introgressed regions in the genomes of admixed Brown Norway rats. Intriguing, genes related to chemical communications among these introgressed regions appeared to contribute to the population-specific adaptations of the admixed Brown Norway rats. Our data reveals evolutionary history of the Brown Norway rat, and offers new insights into the role of climatic changes in speciation of animals and the effect of interspecies introgression on animal adaptation.

Quality control (QC) for lab-designed primers is crucial for the success of a polymerase chain reaction (PCR). Here, we present MFEprimer-3.0, a functional primer quality control program for checking non-specific amplicons, dimers, hairpins and other parameters. The new features of the current version include: (i) more sensitive binding site search using the updated k-mer algorithm that allows mismatches within the k-mer, except for the first base at the 3′ end. The binding sites of each primer with a stable 3′ end are listed in the output; (ii) new algorithms for rapidly identifying self-dimers, cross-dimers and hairpins; (iii) the command-line version, which has an added option of JSON output to enhance the versatility of MFEprimer by acting as a QC step in the ‘primer design → quality control → redesign’ pipeline; (iv) a function for checking whether the binding sites contain single nucleotide polymorphisms (SNPs), which will affect the consistency of binding efficiency among different samples. In summary, MFEprimer-3.0 is updated with the well-tested PCR primer QC program and it can be integrated into various PCR primer design applications as a QC module. The MFEprimer-3.0 server is freely accessible without any login requirement at: https://mfeprimer3.igenetech.com/ and https://www.mfeprimer.com/. The source code for the command-line version is available upon request.

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Transcription factors bind to the genome by forming specific contacts with the primary DNA sequence; however, RNA-binding proteins (RBPs) have greater scope to achieve binding specificity through the RNA secondary structure. It has been revealed that single nucleotide variants (SNVs) that alter RNA structure, also known as RiboSNitches, exhibit 3-fold greater local structure changes than replicates of the same DNA sequence, demonstrated by the fact that depletion of RiboSNitches could result in the alteration of specific RNA shapes at thousands of sites, including 3′ UTRs, binding sites of microRNAs and RBPs. However, the network between SNVs and post-transcriptional regulation remains unclear. Here, we developed RBP-Var, a database freely available at http://www.rbp-var.biols.ac.cn/, which provides annotation of functional variants involved in post-transcriptional interaction and regulation. RBP-Var provides an easy-to-use web interface that allows users to rapidly find whether SNVs of interest can transform the secondary structure of RNA and identify RBPs whose binding may be subsequently disrupted. RBP-Var integrates DNA and RNA biology to understand how various genetic variants and post-transcriptional mechanisms cooperate to orchestrate gene expression. In summary, RBP-Var is useful in selecting candidate SNVs for further functional studies and exploring causal SNVs underlying human diseases.

Spondylolysis is a fracture in part of the vertebra with a reported prevalence of about 3–6% in the general population. Genetic etiology of this disorder remains unknown. The present study was aimed at identifying genomic mutations in patients with dysplastic spondylolysis as well as the potential pathogenesis of the abnormalities. Whole-exome sequencing and functional analysis were performed for patients with spondylolysis. We identified a novel heterozygous mutation (c.2286A > T; p.D673V) in the sulfate transporter gene SLC26A2 in five affected subjects of a Chinese family. Two additional mutations (e.g., c.1922A > G; p.H641R and g.18654T > C in the intron 1) in the gene were identified by screening a cohort of 30 unrelated patients with the disease. In situ hybridization analysis showed that SLC26A2 is abundantly expressed in the lumbosacral spine of the mouse embryo at day 14.5. Sulfate uptake activities in CHO cells transfected with mutant SLC26A2 were dramatically reduced compared with the wild type, confirming the pathogenicity of the two missense mutations. Further analysis of the gene–disease network revealed a convergent pathogenic network for the development of lumbosacral spine. To our knowledge, our findings provide the first identification of autosomal dominant SLC26A2 mutations in patients with dysplastic spondylolysis, suggesting a new clinical entity in the pathogenesis of chondrodysplasia involving lumbosacral spine. The analysis of the gene–disease network may shed new light on the study of patients with dysplastic spondylolysis and spondylolisthesis as well as high-risk individuals who are asymptomatic.

The Ten Eleven Translocation 1 (TET1) protein is a DNA demethylase that regulates gene expression through altering statue of DNA methylation. However, recent studies have demonstrated that TET1 could modulate transcriptional expression independent of its DNA demethylation activity; yet, the detailed mechanisms underlying TET1's role in such transcriptional regulation remain not well understood. Here, we uncovered that Tet1 formed a chromatin complex with histone acetyltransferase Mof and scaffold protein Sin3a in mouse embryonic stem cells by integrative genomic analysis using publicly available ChIP-seq data sets and a series of in vitro biochemical studies in human cell lines. Mechanistically, the TET1 facilitated chromatin affinity and enzymatic activity of hMOF against acetylation of histone H4 at lysine 16 via preventing auto-acetylation of hMOF, to regulate expression of the downstream genes, including DNA repair genes. We found that Tet1 knockout MEF cells exhibited an accumulation of DNA damage and genomic instability and Tet1 deficient mice were more sensitive to x-ray exposure. Taken together, our findings reveal that TET1 forms a complex with hMOF to modulate its function and the level of H4K16Ac ultimately affect gene expression and DNA repair.