TAOK1 science

In brief

This page is the most comprehensive place on our website — a complete overview of what science knows today about the TAOK1 gene, the protein it encodes, and TAOK1-associated neurodevelopmental disorder (TAOK1-NDD). We have gathered here the findings of scientific publications from 1998–2025: from the discovery of the kinase itself, through its role in the cell and in the developing brain, to the latest clinical studies and open research questions. The page is addressed both to parents who want to know everything and to clinicians, scientists, and students. The full bibliography with links is at the bottom.

If you are looking for a more accessible introduction, start with the “What is TAOK1?” page — and come back here when you are ready for a deeper dive.

The gene and the protein: molecular basics

The TAOK1 gene is located on chromosome 17 and encodes the TAO1 protein — a serine/threonine kinase 1,001 amino acids long (hence the name: Thousand And One amino acid Kinase). The protein itself was first isolated and described in 1998, long before it was linked to any human disease. TAO1 belongs to the MAP3K family (mitogen-activated protein kinase kinase kinases) within the group of Ste20-like kinases. In mammals, the TAO family comprises three related proteins: TAOK1, TAOK2, and TAOK3 — with partially overlapping but not identical functions.

TAOK1 expression is particularly high in the brain, which corresponds well with the neurodevelopmental character of the disease caused by variants in this gene.

What does TAO1 kinase do in the cell?

Decades of basic research have built up a picture of a protein with a surprising number of functions. The best documented are:

Signal transduction in MAPK cascades. TAO kinases act at the top of stress-activated kinase cascades: TAOK1, 2, and 3 regulate the p38 MAPK pathway, and TAOK1 and 2 additionally modulate the SAPK/JNK cascade. These pathways control the cell’s response to stress, its growth, differentiation, and survival.

Regulation of the Hippo pathway. TAO kinases also participate in the Hippo pathway — a key mechanism controlling cell proliferation, apoptosis, and organ size. Studies of the Hippo interactome have shown that TAOK1 and TAOK3 can directly phosphorylate the MST2 and LATS1/2 kinases, acting in parallel branches of this pathway.

Cytoskeleton and microtubule stability. TAO1 (also described in the older literature as MARKK) regulates the dynamics of microtubules — the cell’s internal “scaffolding.” It does so, among other ways, through phosphorylation of the MARK2 kinase, which in turn leads to the detachment of the tau protein (MAPT) from microtubules. Interestingly, TAOK1 and TAOK2 play opposing roles here: TAOK1 acts to destabilize microtubules, whereas TAOK2 can bind them directly and stabilize them. TAO kinases also affect the actin cytoskeleton.

DNA damage response and apoptosis. TAOK1 participates in the G2 DNA damage checkpoint of cell division and regulates the morphological changes that occur during programmed cell death (via activation of the JNK cascade).

Plasma membrane remodeling. In 2023, a study published in Science Signaling — notably, conducted precisely on variants derived from patients with TAOK1-NDD — revealed an entirely new function of the protein: TAO1 acts as a plasma membrane remodeling kinase, and disease variants disrupt this activity. This is an example of how studying a rare disease expands fundamental knowledge of cell biology.

TAOK1 in the developing brain

Research on the role of TAOK1 in neurons is key to understanding the disease. An international study from 2021 (van Woerden et al.), combining clinical data with experiments in animal and cell models, showed that TAOK1 is essential for neuronal maturation and the development of the cerebral cortex — silencing the gene during development disrupted the migration of neurons to the correct cortical layers and the development of the dendritic tree, the branches through which a neuron receives signals. Even earlier, in the first clinical paper from 2019, the Dulovic-Mahlow team used fruit fly (Drosophila melanogaster) models with the gene silenced to confirm its importance for the nervous system.

A clinical confirmation of these mechanisms is worth noting: in 2024, the first patient with TAOK1-NDD and periventricular nodular heterotopia was described — a neuronal migration disorder visible on magnetic resonance imaging, whose existence in humans had previously been predicted precisely by animal models.

Clinical genetics: how TAOK1-NDD was discovered

The road from gene to recognizable disease entity was fast by the standards of medicine — here are its milestones:

Before 2019: individual TAOK1 variants appeared in large sequencing studies of people with neurodevelopmental disorders (including Xie et al. 2016), but the gene did not yet have the status of a disease gene.

2019: Dulovic-Mahlow et al. publish in the American Journal of Human Genetics a description of the first patients with de novo TAOK1 variants and neurodevelopmental disorders, identifying TAOK1 as a new disease gene.

2020–2022: large-scale studies of autism genetics independently confirm the gene’s significance. In a two-stage analysis of 42,607 ASD cases (Zhou et al. 2022), TAOK1 reaches exome-wide statistical significance. The gene enters the SFARI Gene database cataloguing autism-associated genes.

2021: van Woerden et al. (Human Mutation) define the core phenotype of the condition and provide mechanistic evidence. The disorder receives its own number in the OMIM classification (#619575, DDIB).

2022: Hunter et al. (Cold Spring Harbor Molecular Case Studies) describe the first familial cases — including siblings with a variant inherited from a mildly affected mother — documenting incomplete penetrance and variable expressivity. The same year brings the first prenatal description: a fetus with a de novo variant and dilation of a lateral ventricle of the brain.

2023: the description of a patient whose dominant symptom was childhood-onset tremor (Blaschek et al.) broadens the spectrum of the condition; the authors propose that TAOK1 be considered in the differential diagnosis of childhood tremor disorders. A separate paper describes fetal macrocephaly in the third trimester as a prenatal phenotype of TAOK1-NDD.

2024: the first description of a neuronal migration disorder (periventricular nodular heterotopia) in a patient with TAOK1-NDD (Cavalli et al., BMC Medical Genomics). A major review of TAO kinases in neurological disorders is also published (Science Signaling).

2025: Elkhateeb et al. publish in Genetics in Medicine the largest cohort to date — 50 patients and 37 unique variants (including 30 novel ones) — refining the frequencies of symptoms and delineating TAOK1-NDD from the related TAOK2-associated disorder.

Disease mechanism: what we know about the variants

The mechanistic picture emerging from the literature:

  • Haploinsufficiency as the main mechanism. Most described variants are protein-truncating changes (nonsense, frameshift, splice-affecting) and deletions. Functional studies showing reduced expression or loss of protein support haploinsufficiency of TAOK1 as the mechanism of disease — this is how the evidence is summarized by the expert ClinGen dosage sensitivity curation.
  • Missense variants clustered in the kinase domain. In the 2025 cohort, most missense variants were located in the protein’s kinase domain, at positions intolerant to change — indicating that the loss of enzymatic activity is central to the disease.
  • Functional evidence at the cellular level. A 2023 study showed directly that patient-derived variants disrupt the protein’s function in plasma membrane remodeling — connecting clinical genetics with a molecular mechanism.
  • De novo and inherited. Most variants arise de novo, but familial transmission with incomplete penetrance and variable expressivity has also been documented — the same change can produce vastly different severity of symptoms even within one family.

The clinical picture in light of the data

The most up-to-date figures come from the cohort of 50 patients (Elkhateeb et al., 2025), compared with 38 previously described cases: neurodevelopmental abnormalities occurred in 100% of patients, macrocephaly in 83%, hypotonia in 58%, and autism spectrum disorder or autistic traits in approx. 31%. Epileptic seizures were reported rarely (4 out of 50 patients, including one with a co-existing second genetic diagnosis). In neuroimaging, the most common abnormality was ventriculomegaly; in many patients, brain imaging remains normal. The core phenotype — consistently described since 2021–2022 — additionally includes: subtle facial dysmorphic features, feeding difficulties in infancy, global developmental delay, joint laxity, and behavioral problems (ADHD, anxiety). The 2025 study added episodes of hypoglycemia and genital anomalies in boys to the clinical picture.

You will find a detailed, accessible discussion of the symptoms on the “What is TAOK1?” page.

TAOK1 beyond the neurodevelopmental disorder

The science of TAO kinases extends beyond TAOK1-NDD — and these broader threads may matter for our community as well. Literature reviews indicate that dysregulation of TAO kinase-related pathways is being studied in the context of neurodegenerative diseases (via the TAO1–MARK–tau axis, relevant in Alzheimer’s disease), cancer, and inflammatory and immune disorders, among others. Work is also underway on selective TAO kinase inhibitors. For a rare disease, this is good news: the more fields of medicine take an interest in a given protein, the faster the knowledge and the set of research tools grow — tools that research on TAOK1-NDD can draw on as well.

Open research questions

An honest overview of the science must also point out what we do not yet know. The most important open questions include:

  • Genotype–phenotype correlation — do the type and location of a variant predict the severity of symptoms? The cohorts described so far are still too small to answer this.
  • Incomplete penetrance — why does the same change produce clear symptoms in one person and almost none in another? What genetic or environmental factors determine this?
  • Natural history — how does the condition unfold over a whole lifetime? The vast majority of described patients are children; data on adults are virtually nonexistent. This is a gap we want to fill with our patient registry and natural history study.
  • Repair mechanisms — which of the effects of TAO1 deficiency are potentially reversible, and within what developmental window? This question is fundamental for future therapies.
  • Biomarkers and endpoints — what measurable indicators will make it possible in the future to assess the effectiveness of a treatment in a clinical trial?

The mission of CureTAOK1 is to support research that will answer these questions. If you are a scientist interested in TAOK1 — contact us at contact@curetaok1.org.

Key databases

For clinicians and researchers, we gather curated TAOK1 resources in one place:

  • *OMIM 610266 — the TAOK1 gene record (research history, described allelic variants);
  • OMIM #619575 — the disease entity record (DDIB);
  • ClinGen — expert dosage sensitivity assessment of the gene (haploinsufficiency);
  • ClinVar — the public database of TAOK1 variants with their clinical classifications;
  • SFARI Gene — the TAOK1 profile in the database of autism-associated genes;
  • GeneCards — the consolidated molecular profile of the gene and protein.

Links to all databases are in the bibliography below.

Bibliography

Clinical publications

  1. Elkhateeb N. et al. Expanding the phenotype and genotype spectrum of TAOK1 neurodevelopmental disorder and delineating TAOK2 neurodevelopmental disorder. Genetics in Medicine, 2025;27(3). https://www.gimjournal.org/article/S1098-3600(24)00282-X/fulltext
  2. Cavalli A. et al. Heterozygous truncating variant of TAOK1 in a boy with periventricular nodular heterotopia: a case report and literature review of TAOK1-related neurodevelopmental disorders. BMC Medical Genomics, 2024. https://link.springer.com/article/10.1186/s12920-024-01840-8
  3. Blaschek A. et al. (2023) — description of a patient with childhood-onset tremor and a de novo TAOK1 variant; discussed in the OMIM *610266 record. https://www.omim.org/entry/610266
  4. Liu C.Y. et al. Fetal macrocephaly in the third trimester: Prenatal phenotype of TAOK1-associated neurodevelopmental disorder. European Journal of Obstetrics & Gynecology and Reproductive Biology, 2023. https://pubmed.ncbi.nlm.nih.gov/37696715/
  5. Paternal De Novo Variant of TAOK1 in a Fetus With Structural Brain Abnormalities. 2022. https://pmc.ncbi.nlm.nih.gov/articles/PMC9343781/
  6. Hunter J.M. et al. Inherited and de novo variants extend the etiology of TAOK1-associated neurodevelopmental disorder. Cold Spring Harbor Molecular Case Studies, 2022;8(2). https://pmc.ncbi.nlm.nih.gov/articles/PMC8958914
  7. Zhou X. et al. (2022) — a two-stage analysis of de novo and inherited variants in 42,607 individuals with ASD; TAOK1 among genes reaching exome-wide significance (discussed at SFARI Gene). https://gene.sfari.org/database/human-gene/TAOK1
  8. van Woerden G.M. et al. TAOK1 is associated with neurodevelopmental disorder and essential for neuronal maturation and cortical development. Human Mutation, 2021;42(4). https://onlinelibrary.wiley.com/doi/full/10.1002/humu.24176
  9. Dulovic-Mahlow M. et al. De Novo Variants in TAOK1 Cause Neurodevelopmental Disorders. American Journal of Human Genetics, 2019. https://www.sciencedirect.com/science/article/pii/S0002929719301910

Basic biology and reviews

  1. Byeon S., Yadav S. Pleiotropic functions of TAO kinases and their dysregulation in neurological disorders. Science Signaling, 2024;17(817). https://www.science.org/doi/10.1126/scisignal.adg0876
  2. Beeman N., Sapre T., Ong S.E., Yadav S. Neurodevelopmental disorder-associated mutations in TAOK1 reveal its function as a plasma membrane remodeling kinase. Science Signaling, 2023;16(766). https://pubmed.ncbi.nlm.nih.gov/36595571/
  3. Clinical and Neurobiological Aspects of TAO Kinase Family in Neurodevelopmental Disorders. Frontiers in Molecular Neuroscience, 2021. https://www.frontiersin.org/journals/molecular-neuroscience/articles/10.3389/fnmol.2021.655037/full
  4. Fang C.-Y. et al. The Diverse Roles of TAO Kinases in Health and Diseases. International Journal of Molecular Sciences, 2020;21(20). https://www.mdpi.com/1422-0067/21/20/7463

Databases

  1. OMIM *610266 — TAO Kinase 1 (gene record). https://www.omim.org/entry/610266
  2. OMIM #619575 — Developmental delay with or without intellectual impairment or behavioral abnormalities (DDIB). https://omim.org/entry/619575
  3. ClinGen — TAOK1 dosage sensitivity curation. https://search.clinicalgenome.org/kb/gene-dosage/HGNC:29259
  4. SFARI Gene — TAOK1 gene profile. https://gene.sfari.org/database/human-gene/TAOK1
  5. GeneCards — TAOK1 gene profile. https://www.genecards.org/card/TAOK1

Materials for families

  1. Unique — Rare Chromosome Disorder Support Group: TAOK1-related neurodevelopmental disorder (family guide, 2025). https://rarechromo.org/media/singlegeneinfo/Single%20Gene%20Disorder%20Guides/TAOK1-related%20neurodevelopmental%20disorder%20FTNW.pdf

This content is for informational purposes only and does not replace medical advice. Last updated: August 2026.