The Fragile X Syndrome – Where Do We Go?

  • 23k

    Total downloads

  • 112k

    Total views and downloads

About this Research Topic

Submission closed

Background

Affecting about 1 in 4000 males and 7000 females, the Fragile X Syndrome (FXS) represents the most common form of inherited mental retardation in all human populations and ethnic groups. Impaired individuals display a variety of intellectual deficits ranging from mild learning handicaps to severe cognitive disabilities with IQs as low as 40-50, but also autistic behaviours as well as epileptic seizures characterize the disease.

The complaints are caused by the loss of a single protein, the Fragile X Mental Retardation Protein FMRP, which functions to regulate the mRNA metabolism in various aspects. Studies demonstrated that FMRP is able to associate with a diversity of mRNAs -approximately 4% of all mRNAs in the mammalian brain- by interacting with several different RNA-motifs. Thereby, FMRP regulates not only mRNA transport and stability of its partner mRNAs, but also mRNA translation. Since G-quartets present in the mRNA of FMRP were found to function as exonic splicing enhancers, FMRP was also suggested to take action in alternative splicing.

On the other hand, FMRP itself turned out to be under control of signalling cascades of group 1 metabotropic glutamate receptors (gp1 mGluRs; mGluR1&5), hence allowing for an activity dependent regulation of the mRNA metabolism in various aspects by FMRP. Subsequent studies gave rise to the mGluRTheory of FXS: The theory states that FMRP normally acts as a repressor of mRNA translation downstream of gp1 mGluRs, which is released after mGluR activation and thereby induces the translation of proteins required for the expression of LTD. Hence, in the absence of FMRP, persistent and mGluR stimulation independent synthesis of LTD-proteins causes ongoing AMPAR internalization.

Indeed, there is good evidence for this theory. The use of the mGluR5 antagonist MPEP has been shown to improve many symptoms of FXS in FMR1-/- mice, a model of the disease. These promising results have prompted clinical trials with mGluR antagonists to downregulate mGluR signalling, but although patients treated with these substances were initially reported to experience some behavioural improvements, all trials were discontinued during phases IIb/III since the studies did not show any significant improvements in abnormal behaviours compared to placebo.

Since then, research has been continuing, and in line with the complexity of the disease, various directions are being explored including Metalloproteinase function, GABAa signalling, the role of glia cells, mechanisms of neurogenesis and neurodevelopment and many more. However, the contributions of most of these mechanisms to the specific symptoms of FXS have often remained elusive, and the translations of findings from mouse to men challenging.

We would like to bring together new findings, ideas, comments, thoughts and perspectives from all kind of different research areas of the field to stimulate discussions and improve our understanding of this exceptional disease. We welcome studies using humans, animal models or basic research techniques and encourage submissions of all article types such as Original Research (positive and/or negative results), Methods, Hypothesis & Theory, Clinical studies, Reviews and Comments. Short Communications providing a comprehensive analysis of any topic of interest are very welcome.

Research Topic Research topic image

Keywords: Fragile X Syndrome, FXS, inherited mental retardation, FMRP, Autism Spectrum Disorder

Important note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.

Frequently asked questions

  • Frontiers' Research Topics are collaborative hubs built around an emerging theme.Defined, managed, and led by renowned researchers, they bring communities together around a shared area of interest to stimulate collaboration and innovation.

    Unlike section journals, which serve established specialty communities, Research Topics are pioneer hubs, responding to the evolving scientific landscape and catering to new communities.

  • The goal of Frontiers' publishing program is to empower research communities to actively steer the course of scientific publishing. Our program was implemented as a three-part unit with fixed field journals, flexible specialty sections, and dynamically emerging Research Topics, connecting communities of different sizes and maturity.

    Research Topics originate from the scientific community. Many of our Research Topics are suggested by existing editorial board members who have identified critical challenges or areas of interest in their field.

  • As an editor, Research Topics will help you build your journal, as well as your community, around emerging, cutting-edge research. As research trailblazers, Research Topics attract high-quality submissions from leading experts all over the world.

    A thriving Research Topic can potentially evolve into a new specialty section if there is sustained interest and a growing community around it.

  • Each Research Topic must be approved by the specialty chief editor, and it falls under the editorial oversight of our editorial boards, supported by our in-house research integrity team. The same standards and rigorous peer review processes apply to articles published as part of a Research Topic as for any other article we publish.

    In 2023, 80% of the Research Topics we published were edited or co-edited by our editorial board members, who are already familiar with their journal's scope, ethos, and publishing model. All other topics are guest edited by leaders in their field, each vetted and formally approved by the specialty chief editor.

  • Publishing your article within a Research Topic with other related articles increases its discoverability and visibility, which can lead to more views, downloads, and citations. Research Topics grow dynamically as more published articles are added, causing frequent revisiting, and further visibility.

    As Research Topics are multidisciplinary, they are cross-listed in several fields and section journals – increasing your reach even more and giving you the chance to expand your network and collaborate with researchers in different fields, all focusing on expanding knowledge around the same important topic.

    Our larger Research Topics are also converted into ebooks and receive social media promotion from our digital marketing team.

  • Frontiers offers multiple article types, but it will depend on the field and section journals in which the Research Topic will be featured. The available article types for a Research Topic will appear in the drop-down menu during the submission process.

    Check available article types here 

  • Yes, we would love to hear your ideas for a topic. Most of our Research Topics are community-led and suggested by researchers in the field. Our in-house editorial team will contact you to talk about your idea and whether you’d like to edit the topic. If you’re an early-stage researcher, we will offer you the opportunity to coordinate your topic, with the support of a senior researcher as the topic editor. 

    Suggest your topic here 

  • A team of guest editors (called topic editors) lead their Research Topic. This editorial team oversees the entire process, from the initial topic proposal to calls for participation, the peer review, and final publications.

    The team may also include topic coordinators, who help the topic editors send calls for participation, liaise with topic editors on abstracts, and support contributing authors. In some cases, they can also be assigned as reviewers.

  • As a topic editor (TE), you will take the lead on all editorial decisions for the Research Topic, starting with defining its scope. This allows you to curate research around a topic that interests you, bring together different perspectives from leading researchers across different fields and shape the future of your field. 

    You will choose your team of co-editors, curate a list of potential authors, send calls for participation and oversee the peer review process, accepting or recommending rejection for each manuscript submitted.

  • As a topic editor, you're supported at every stage by our in-house team. You will be assigned a single point of contact to help you on both editorial and technical matters. Your topic is managed through our user-friendly online platform, and the peer review process is supported by our industry-first AI review assistant (AIRA).

  • If you’re an early-stage researcher, we will offer you the opportunity to coordinate your topic, with the support of a senior researcher as the topic editor. This provides you with valuable editorial experience, improving your ability to critically evaluate research articles and enhancing your understanding of the quality standards and requirements for scientific publishing, as well as the opportunity to discover new research in your field, and expand your professional network.

  • Yes, certificates can be issued on request. We are happy to provide a certificate for your contribution to editing a successful Research Topic.

  • Research Topics thrive on collaboration and their multi-disciplinary approach around emerging, cutting-edge themes, attract leading researchers from all over the world.

  • As a topic editor, you can set the timeline for your Research Topic, and we will work with you at your pace. Typically, Research Topics are online and open for submissions within a few weeks and remain open for participation for 6 – 12 months. Individual articles within a Research Topic are published as soon as they are ready.

    Find out more about our Research Topics

  • Our fee support program ensures that all articles that pass peer review, including those published in Research Topics, can benefit from open access – regardless of the author's field or funding situation.

    Authors and institutions with insufficient funding can apply for a discount on their publishing fees. A fee support application form is available on our website.

  • In line with our mission to promote healthy lives on a healthy planet, we do not provide printed materials. All our articles and ebooks are available under a CC-BY license, so you can share and print copies.