Shared Neurobiology of Fragile X Syndrome and Autism (R21) | Apply Online

FAQs: Shared Neurobiology of Fragile X Syndrome and Autism (R21) (PA-06-430)

What is the NIH funding opportunity PA-06-430 about?

This NIH Funding Opportunity Announcement (FOA), titled "Shared Neurobiology of Fragile X Syndrome and Autism (R21)," supports early-stage, exploratory research that aims to identify biological overlap between Fragile X syndrome (FXS) and autism, including autism spectrum disorders such as Rett syndrome. The emphasis is on moving beyond symptom description to clarify shared causes (etiology) and disease processes (pathophysiology) that could reveal actionable therapeutic targets.

What does the R21 mechanism mean in this FOA?

The R21 mechanism is intended for exploratory/developmental projects. In this context, it is designed to support high-impact, early-stage research that can generate proof-of-concept data, open new research directions, and accelerate novel ideas, rather than fund large, fully mature research programs.

What is the central goal of the research encouraged by this FOA?

The core goal is to pin down shared neurobiological mechanisms between FXS and autism by linking molecules to cells to circuits to behavior. Projects are especially encouraged when they can point to concrete therapeutic targets that might benefit both conditions through shared pathways.

Why does NIH emphasize overlap between Fragile X syndrome and autism?

The FOA highlights well-recognized clinical and behavioral overlap. It notes that a measurable fraction of individuals with autistic features have FXS (approximately 2.5 to 6 percent), and that a substantial minority of children with FXS meet criteria for autism (around 15 to 25 percent). The FOA also notes that many more children with FXS show autism-like traits, with estimates as high as 50 to 90 percent showing some associated features. The program rationale is that these shared features may reflect shared underlying neural mechanisms, not just similar outward behaviors.

What kinds of autism-like traits in FXS are cited in the FOA?

Examples listed include reduced eye contact, repetitive or stereotyped behaviors (such as hand flapping and hand biting), speech perseveration and other language abnormalities, sensory issues such as tactile defensiveness and hyperarousal, developmental delay and moderate-to-severe intellectual disability, and social anxiety with mood lability.

What scientific approaches does the FOA encourage?

The FOA leans toward basic and translational neuroscience approaches that connect molecular and cellular findings to neural networks, circuits, and behavior. It points to rapid progress in FXS research using model systems (including mice and flies) where investigators can assess subcellular/cellular changes and scale up to intercellular networks and circuits, and it encourages using these tools to test what aspects of FXS neurobiology also explain autism-relevant biology.

Does the FOA require the project to focus on shared mechanisms rather than parallel studies?

Yes. Responsive applications are expected to center on overlap. The FOA indicates that proposals should not treat FXS and autism as separate topics running in parallel; instead, applicants should make the case for a shared mechanism and design experiments to test that shared mechanism.

Are studies in humans allowed under this FOA?

Yes. Studies may be conducted in humans, animals, or both. For human subjects studies, the FOA specifically encourages inclusion of children affected by both FXS and autism, because that population may be particularly informative for identifying common mechanisms.

Are animal model studies allowed, and which model systems are mentioned?

Yes. The FOA allows multiple animal model systems and explicitly mentions mouse, fly, and zebrafish. It emphasizes that basic neuroscience studies in these systems should address both FXS and autism-related biology, rather than focusing on FXS alone.

What makes an application "responsive" to this FOA?

Applications are responsive when they focus on understanding neural pathways, circuits, systems, and molecules involved in FXS that may also be implicated in autism (including Rett syndrome), and when they directly test shared mechanisms relevant to both conditions. Strongly encouraged projects are those that identify novel drug targets and lay groundwork for therapeutics that could plausibly benefit both FXS and autism.

What types of projects are considered a poor fit for this FOA?

Projects that are more exclusively focused on autism without a clear and substantive connection to FXS mechanisms are described as better suited to other NIH program announcements dedicated to autism and autism spectrum disorders (PA-06-390, PA-06-391, or PA-06-392). The niche of PA-06-430 is the shared neurobiology angle, particularly where FXS research can inform autism mechanisms and autism-relevant endpoints can sharpen understanding of FXS.

What is the award ceiling for this R21 opportunity?

The FOA lists an award ceiling of $200,000.

Is cost sharing or matching required?

No. The FOA states there is no cost-sharing or matching requirement.

Which CFDA numbers are associated with this funding opportunity?

The FOA is associated with CFDA 93.242 (Mental Health Research Grants), 93.853 (Extramural Research Programs in the Neurosciences and Neurological Disorders), and 93.865 (Child Health and Human Development Extramural Research).

Who is eligible to apply?

Eligibility is broad and includes public and private institutions of higher education; nonprofits (with or without 501(c)(3) status); state and local governments; tribal governments and organizations; independent school districts; public housing authorities/Indian housing authorities; special district governments; and for-profit organizations other than small businesses. The FOA also states that foreign institutions are eligible, eligible federal agencies may apply, and faith-based or community-based organizations can apply.

Are foreign institutions eligible?

Yes. The FOA explicitly states that foreign institutions are eligible to apply.

Can for-profit organizations apply?

Yes. For-profit organizations other than small businesses are listed as eligible applicants.

Can an applicant submit more than one application?

Yes. Applicants may submit more than one application as long as each application is scientifically distinct.

When was this FOA posted, and is it still active?

The FOA was posted on May 24, 2006. It used multiple receipt dates and listed a final closing date of September 7, 2009, with an archive date of October 7, 2009. Based on those dates, it is no longer active, but it remains a useful historical example of NIH priorities around shared mechanisms and therapeutic target discovery.

Does the FOA explicitly include Rett syndrome within scope?

Yes. The FOA references autism spectrum disorders such as Rett syndrome and includes Rett syndrome within the framing of autism-related biology for overlap-focused studies.

What is the key therapeutic emphasis in this FOA?

The FOA places strong emphasis on studies that can identify novel drug targets and provide a foundation for therapeutics that could plausibly benefit both FXS and autism by acting on shared biological pathways.