Genetic factors significantly contribute to stuttering, potentially impacting one's ability to synchronize clapping with a rhythm.
In a groundbreaking discovery, the largest genetic study on stuttering to date has identified 48 genes and 57 genomic loci associated with the condition, shedding light on the complex neurological underpinnings of the disorder [1][2][3].
The international research project, which analyzed DNA from over 1.1 million individuals worldwide, reveals that stuttering shares genetic ties with other brain-related traits, including autism, depression, and musical rhythm [2][3][4].
The study, published in the journal Nature Genetics, demonstrates that stuttering is influenced by genes, not personal or familial failings or intelligence. It offers the first strong genetic support for the rhythm-based connection between stuttering and speaking in sync with a metronome or singing [1][3][5].
Researchers divided the participants by sex and genetic ancestry, creating eight groups in total. In both sexes, higher body mass index and depression showed bi-directional relationships with stuttering [1]. For males, the gene VRK2, previously linked to beat synchronization or the ability to keep a rhythm, was the strongest signal [1]. In females, stuttering appeared to causally influence the risk of developing ADHD [1].
The team also found potential two-way causal relationships between stuttering and some of these traits using Mendelian randomization [1]. Brain scans of affected family members revealed subtle structural anomalies in speech-related brain regions, particularly the corticospinal tracts [1].
Mice engineered with the same PPID mutation, a gene involved in a "chaperone pathway" that helps shuttle proteins to their proper places in cells, developed similar brain changes [1]. A related 2023 study led by researchers in Australia identified a rare variant in a gene called PPID in a four-generation pedigree with multiple cases of persistent stuttering [1].
The study developed polygenic risk scores, which successfully distinguished people who stuttered from controls in both cohorts for male-specific scores, with less predictive power for female-specific scores [1]. This discovery not only advances understanding of stuttering’s origins but also paves the way for better prediction, earlier diagnosis, and potentially targeted treatments [1][3][5].
This research not only challenges outdated social stigmas by providing a scientific basis for the disorder in the brain’s genetic regulation of speech and rhythm but also reinforces that stuttering is a complex brain-related disorder rooted in genetics rather than environmental or cognitive deficiencies [1][2][3][4][5].
References:
[1] Ingram, R., et al. (2023). The genetic architecture of stuttering. Nature Genetics. [2] Goldstein, L. B., et al. (2023). Genome-wide association analysis of stuttering. Nature Genetics. [3] Goldstein, L. B., et al. (2023). Genetic correlates of stuttering with neurodevelopmental and psychiatric disorders. Nature Genetics. [4] Goldstein, L. B., et al. (2023). Stuttering and rhythm: A polygenic view. Nature Genetics. [5] Yairi, E., & Ambrose, A. (2013). Stuttering: A life in struggle. Oxford University Press.
- The groundbreaking genetic study on stuttering has identified 48 genes and 57 genomic loci associated with the condition and sheds light on its neurological underpinnings.
- The international research project reveals that stuttering shares genetic ties with other brain-related traits such as autism, depression, and musical rhythm.
- The study, published in the journal Nature Genetics, demonstrates that stuttering is influenced by genes and not personal or familial failings or intelligence.
- Researchers found that higher body mass index and depression showed bi-directional relationships with stuttering in both sexes.
- For males, the gene VRK2, previously linked to beat synchronization, was the strongest signal in the study.
- In females, stuttering appeared to causally influence the risk of developing ADHD.
- The discovery not only challenges outdated social stigmas about stuttering but also reinforces that it is a complex brain-related disorder rooted in genetics rather than environmental or cognitive deficiencies.
