Background & aims: Developmental stuttering is a neurodevelopmental speech disorder characterised by involuntary interruptions to speech fluency. Although most cases of stuttering are likely underpinned by polygenic factors, there is growing evidence that monogenic explanations exist for a proportion of individuals who stutter. Some genetic aetiologies implicated in stuttering are also associated with more complex neurodevelopmental presentations. Despite our expanding understanding of the genetic architecture of stuttering, there is yet to be a systematic review that examines all known genetic aetiologies associated with the condition.
Methods: A protocol for this review was registered in PROSPERO (CRD420251173194). A comprehensive literature search for published, peer-reviewed studies where developmental stuttering is linked to a confirmed or likely pathogenic genetic aetiology was conducted in October 2025. The electronic databases MEDLINE (Ovid), Embase, and Web of Sciences were systematically searched. The 200 most relevant results from an additional Google Scholar search were also included. Animal studies were excluded from the search.
Preliminary results/conclusions: The search yielded 2225 studies following duplicate removal. Following screening procedures, included studies will be evaluated using Q-Genie, a critical appraisal tool designed for genetic association studies. Data extracted will include stuttering prevalence where possible to determine, descriptions of stuttering phenotypes, and information regarding co-occurring conditions. Any overlap between genes implicated in stuttering and more complex neurodevelopmental presentations will be reported. Trends in gene location and biological function of genes implicated in stuttering will also be analysed.
This review will be the first to systematically examine all genetic aetiologies associated with stuttering as reported in the literature. This will provide a foundation for further single gene discovery work to strengthen our understanding of monogenic explanations for stuttering.