No abstract

Charcot-Marie-Tooth (CMT) neuropathies are amongst the most common inherited diseases in neurology. While great strides have been made to identify the genesis of these diseases, a diagnostic gap of 30-60% remains. Classic models of genetic causation may be limited to fully close this gap and, thus, we review the current state and future role of alternative, non-Mendelian forms of genetics in CMT. Promising synergies exist to further define the full genetic architecture of inherited neuropathies, including affordable whole-genome sequencing, increased data aggregation and clinical collaboration, improved bioinformatics and statistical methodology, and vastly improved computational resources. Given the recent advances in genetic therapies for rare diseases, it becomes a matter of urgency to diagnose CMT patients with great fidelity. Otherwise, they will not be able to benefit from such therapeutic options, or worse, suffer harm when pathogenicity of genetic variation is falsely evaluated. In addition, the newly identified modifier and risk genes may offer alternative targets for pharmacotherapy of inherited and, potentially, even acquired forms of neuropathies. Genetics of Charcot-Marie-Tooth DiseaseAs with many other Mendelian diseases, the introduction of next generation sequencing (NGS) revolutionized the genetic diagnosis of Charcot-Marie-Tooth disease with now over 90 known genes causing CMT. 1,2 Though CMT can be caused by an overwhelming amount of genetic defects, it is noteworthy that a handful of genes are responsible for the majority of cases. More than half of all CMT cases are caused by five genetic mutations: PMP22 duplication (39.5%), PMP22 point mutation (1.4%), GJB1 (10.8%), MFN2 (2.8%), and MPZ (3.1%). 3 For autosomal dominant (AD) demyelinating CMT (CMT1), the most commonly mutated genes are: GJB1, PMP22, MPZ, EGR2, LITAF, NEFL, or PMP2. 3 Unlike CMT1, AD axonal CMT (CMT2) and autosomal recessive (AR) axonal and/or demyelinating forms (CMT4) are caused by many, individually rare, genes that typically

Objective: Ovarian cancer (OvCa) metastasis requires the coordinated motility of both cancer and stromal cells. Cellular movement is a dynamic process that involves the synchronized assembly of f-actin bundles into cytoskeletal protrusions by fascin. Fascin directly binds factin and is an integral component of filopodia, lamellapodia and stress fibers. Here, we examine the expression pattern and function of fascin in the cancer and stromal cells of OvCa tumors. Methods: Fascin expression was evaluated in human cells and tissues using immunohistochemistry and immunofluorescence. The functional role of fascin in cancer and stromal cells was assessed with in vitro functional assays, an ex vivo colonization assay and in

Significant progress has been made in elucidating single nucleotide polymorphism diversity in the human population. However, the majority of the variation space in the genome is structural and remains partially elusive. One form of structural variation is tandem repeats (TRs). Expansion of TRs are responsible for over 40 diseases, but we hypothesize these represent only a fraction of the pathogenic repeat expansions that exist. Here we characterize long or expanded TR variation in 1,115 human genomes as well as a replication cohort of 2,504 genomes, identified using ExpansionHunter Denovo. We found that individual genomes typically harbor several rare, large TRs, generally in non-coding regions of the genome. We noticed that these large TRs are enriched in their proximity to Alu elements. The vast majority of these large TRs seem to be expansions of smaller TRs that are already present in the reference genome. We are providing this TR profile as a resource for comparison to undiagnosed rare disease genomes in order to detect novel disease-causing repeat expansions.